Chapter 14 : Enterprise Computing

What is enterprise computing?

Enterprise computing involves the use of computers in networks,such as LANs and WANs, or a series of interconnected networks that encompass a variety of different operating systems,protocols, and network architectures

Types of enterprises:

• Retai
• Manufacturing
• Service
• Wholesale
• Government
• Educational
• Transportation.

In an enterprise , users typically fall into one of four categories

Executive Management

Middle Management

Operational Management

Non management Employees

-Enterprise information is the information is the information gathered in the ongoing operations of an enterprise-sized organization

• Business intelligence 
• Business process management
• Business process automation

-Managers coordinate resources by performing four activities :

1. Planning
2. Organizing
3. Leading
4. Controlling

Information System in the Enterprise

An information system  is a set of hardware,software,data,people, and procedures that work together to produce information

Functional units within an enterprise might include

• accounting and finance
• human resource
• engineering or product development
• manufacturing
• marketing 
• sales
• distribution
• customer
• information technology

-A human resources information system(HRIS) manages one or more human resources functions 

• Computer-aided design(CAD) uses computers and special software to aid in engineering , drafting , and design
• Computer-aided engineering (CAE) uses computers to test product designs
• Computer-aided manufacturing (CAM) is the use of computers to control production equipment
• Computer-integrated manufacturing (CIM) uses computers to integrate the many different operations of the manufacturing process
• Material Requirements Planning (MRP) uses software to help monitor and control processes related to production
• Manufacturing Resource Planning 11 (MRP11)is an extension of MRP and also includes software that helps in scheduling

-sales force automation(SFA) software equips traveling salespeople with the electronic tools they need to be more productive

Distribution system perform the following functions

• Provide forecasting for inventory control
• Manage and track shipping of products
• Provide information and analysis on inventory in a warehouse

Customer interaction management (CIM) software manages the day-to-day interactions with customers

General purpose information systems generally fall into one of five categories

• office information system 
• transaction processing system 
• management information system
• decision support system
• expert system

Integrated Information Systems

• -Customer relationship management manages information about customer,interactions with customers, past purchases and interests
• Enterprise resource planning provides centralized,integrated software to help mange and coordinate ongoing activities
• Content management system are information system that combine databases ,software, and procedures

Enterprise-Wide Technologies and Methodologies

Some technologies used in enterprises include

• portals
• data warehouses
• electronic data interchange
• extranets
• web services
• document management systems
• workflow
• virtual private networks

A portal is a collection of links, content, and services presented on a Web page that are interesting for a particular job function.

A data warehouse is a huge database that stores manages the data required to analyze historical and current transactions.

EDI is a set of standards that controls the transfer of business data and information among computers both within and among enterprises

An extranet is the portion of a company’s network that allows customers or suppliers of a company to access parts of an enterprise’s intranet

Web services allow businesses to create products and B2B interactions over the Internet.

A document management system (DMS) allows for storage and management of a company's documents.

A workflow is a defined process that identifies the specific set of steps involved in completing a particular project or business process.

A virtual private network (VPN) provides mobile users, vendors, and customers with a secure connection to the company network server.

Virtualization and cloud Computing

Virtualization is the practice of sharing or pooling computing resources.

Server virtualization: Provides the capability to divide a physical server logically into many virtual servers.

Storage virtualization: Provides the capability to create a single logical storage device from many physical storage devices.

Cloud computing is an Internet service that provides computing needs to computer users

Grid computing combines many servers and/or personal computers on a network to act as one large computer

Enterprise Hardware

Enterprise hardware allows large organizations to manage and store information and data using devices geared for: 

• Heavy use
• Maximum availability 
• Maximum efficiency.

RAID duplicates data and implements duplication in different ways.

Network attached storage (NAS) is a server that provides storage to users and information systems attached to the network.

A storage area network (SAN) is a high-speed network that provides storage to other servers to which it attached.

An enterprise storage system is a strategy that focuses on the availability, protection, organization, and backup of storage in a company.

A blade server packs a complete computer server on a single card rather than a system unit.

A thin client is a small terminal-like computer that mostly relies on a server for data storage and processing.

High Availability, Scalability, and Interoperability

A high-availability system continues running and performing tasks for at least 99% of the time.

Scalability is a measure of how well computer hardware, software, or an information system can grow to meet increasing performance demands.

Interoperability is the ability for an information system to share information with other information systems within an enterprise.

Backup Procedures

A disaster recovery plan is a written plan describing the steps a company would take a restore computer operations in the event of a disaster.

-Contains four major components: 

• Emergency plan
• Backup plan
• Recovery plan
• Test plan

Chapter 13 : Computer Programs and Programming Languages

Computer Programs and Programming Languages
A computer program is a series of instructions that directs a computer to perform tasks. 

• Created by a programmer using a programming language.

Low-Level Languages
Machine language is the first generation of programming languages.

Assembly language is the second generation of programming languages.

A source program contains the code to be converted to machine language.

Procedural language
In a procedural language, the programmer writes instructions that tell the computer what to accomplish and how to do it. 

• A compiler translate an entire program before executing it
• An interpreter converts and executes one code statement at a time.

-The C programming language is used to write many of today's programs.

-COBOL (Common) Business-Oriented Language) is designed for business applications, but easy to read because of the English-like statements.

Object-Oriented Programming Languages and Program Development Tools
An object-oriented programming (OOP) language allows programmers the ability to reuse and modify existing objects.

Other advantages include: 

• Objects can be reused
• Work well in a RAD environment
• Programmers create applications faster.
• Most program development tools are IDEs

Java is an object-oriented programming language developed by Sun Microsystems.

The Microsoft .NET Framework allows almost any type of program to run on the Internet or an internal business network, as well as computers and mobile devices.Features include : CLR , Classes

C++ is an extension of the C programming language.

C# is based on C++ and was developed by Microsoft.

F# combines the benefit of an object-oriented language with those of a functional language.

Visual Studio is Microsoft’s suite of program development tools

• Visual Basic is based on the BASIC programming language
• Visual C++ is based on C++
• Visual C# combines the programming elements of C++ with an easier, rapid-development environment

A visual programming language is a language that uses a visual or graphical interface for creating all source code.

Borland’s Delphi is a powerful program development tool that is ideal for building large-scale enterprise and Web applications in a RAD environment

PowerBuilder is a powerful program development RAD tool

A 4GL (fourth-generation language) is a nonprocedural language that enables users and programmers to access data in a database

An application generator is a program that creates source code or machine code from a specification of the required functionality.

A macro is a series of statements that instructs an application how to complete a task.

Web Page Development

HTML is a special formatting language that programmers use to format documents for display on the Web.

XHTML is a markup language that allows Web sites to be displayed more easily on mobile devices

XML allows Webs developers to create customized tags and use predefined tags to display content appropriately on various devices. 

• WML is a subset of XML and is used to design pages for microbrowsers.
• Two application of XML are RSS 2.0 and ATOM.

Dynamic HTML  (DHTML) allows Web developers to include more graphical interest and

interactivity

Ruby on Rails (RoR) provides technologies for developing object-oriented, database-driven Websites

Web 2.0 allows Web sites to provide a means for users to

• Share personal information 
• Allow users to modify Web site content
• Have application software built into the site

Web page authoring software can create sophisticated Web pages that include images, video, audio,

 animation, and other effects

• Dreamweaver 
• Expression web 
• Flash
• Sharepoint designer

Multimedia Program Development

Multimedia authoring software allows programmers, to combine text, graphics, animation, audio, and video in an interactive presentation.

• toolbox
• Director 

Program Development

Program development consists of a series of steps programmers use to build computer programs.

Step 1 - Analyze Requirements
To initiate program development, programmer: i) review the requirements ii) meets with the system analyst and users iii) identifies input, processing, and output.

Step 2- Design Solution

Design solution algorithm

In structured design, the programmer typically begins with a general design and moves toward a more detailed design.

Programmers use a hierarchy chart to show program modules graphically

With object-oriented (OO) design, the programmer packages the data and the program into a single object

A program flowchart graphically shows the logic in a solution algorithm

Flowcharting software makes it easy to modify and update flowcharts.

UML (Unified Modeling Language) has been adopted as a standard notation for object modeling and development.

Step 3 - Validate Design

Check for logic errors using test data.

Step 4 - Implement Design

Implementation of the design includes using a program development tool that assists the programmer by: 

•  generating or providing some or all code 
• Writing the code that translates the design into a computer program 
• Creating the user interface.

Step 5 - Test Solution

The goal of program testing is to ensure the program runs correctly and is error free.

• Errors include syntax errors and logic errors
• Debugging the program involves removing the bugs
• A beta is a program that has most or all of its features and functionality implemented.

Step 6 - Document Solution

In documenting the solution, the programmer performs two activities:

•  Review the program code
• Review all the documentation.

Chapter 12 : Exploring Information System Development

What is System Development?

System development is a set of activities used to build an information system. 

• A system is a set of components that interact to achieve a common goal.
•  An information system (IS) is a collection of hardware, software, data, people, and procedures that work together to produce quality information.
• System development activities are grouped into phases, collectively called the system development life cycle (SDLC)
• System development should follow three general guidelines: 
•  Group activities or tasks into phases 
• involve users 
• define standard

Project management is the process of planning, scheduling, and then controlling the activities during system development

To plan and schedule a project efficiently, the project leader identifies: 

• Project scope
• Required activities
• Order of activities.
• Time estimate for each activity 
• cost estimate for each activity
• order of activity 
• Activities that can take place at the same times

Feasibility is a measure of how suitable the development of a system will be to the organization. 

• Operational feasibility
• Schedule feasibility 
• Technical feasibility
• Economic feasibility

Documentation is the collection and summarization of data and information.

Planning Phase

The planning phase for a project begins when the steering committee receives a project request

Four major activities are performed: 

• Review and approve the project requests 
• Prioritize the project requests
• Allocate resources
• Form a project development team.

Analysis Phase

Conduct a preliminary investigation

• Determines and defines the exact nature of the problem or improvement
• Interview the user who submitted the request
• Perform detailed analysis
• Study how the current system works
• Determine the users’ wants, needs, and requirements
• Recommend a solution

Process modeling (structured analysis and design) is an analysis and design technique that describes processes that transform inputs into output

• An entity-relationship diagram (ERD) is a tool that graphically shows the connections among entities in a system
• A data flow diagram (DFD) is a tool that graphically shows the flow of data in a system
• The project dictionary contains all the documentation and deliverables of a project.

A decision table is a table that lists a variety of conditions and the actions that correspond to each condition

The data dictionary stores the data item's name, description, and other details about each data item

Object modeling combines the data with the processes that act on that data into a single unit, called an object

UML (Unified Modeling Language) has been adopted as a standard notation for object modeling and development.Two diagram include Use case diagram and Class diagram 

• A use case diagram graphically shows how actors (users) interact with the information system.
• A class diagram graphically shows classes and subclasses in a system

Design Phase

The design phase consists of two major activities 

1. Acquire hardware and software
2. Develop all of the details of the new or modified information system

A prototype (proof of concept) is a working model of the proposed system. 

Implementation Phase

The purpose of the implementation phase is to construct the new or modified system and then deliver it. 

• Develop programs > Install and test the new system > Train users > Convert to the new system.

Various tests should be performed on the new system. 

• Unit test - verifies that each individual program or object works by itself.
•  Systems test - verifies that all programs in an application work together properly. 
• Integration test - verifies that an application works with other applications. 
• Acceptance test - checks the new system to ensure that it works with actual data.

Training involves showing users exactly how they will use the new hardware and software in the system.

Operation, Support, and Security Phase

The purpose of the operation, support, and security phase is to provide ongoing assistance for an information system and its users after the system is implemented.

• Perform maintenance activities > Monitor system performance > Assess system security.

A computer security plan should do the following:

•  Identify all information assets of an organization. 
• Identify all security risks that may cause an information asset loss. 
• For each risks, identify the safeguards that exist to detect, prevent, and recover from a loss.

Chapter 11 : Manage Computing Securely, Safely and Ethically

Computer Security Risks

A computer security risk is any event or action that could cause a loss of or damage to computer hardware, software, data, information, or processing capability.

A cybercrime is an online or Internet-based illegal act.

-Hackers

-Crackers

-Script Kiddies

-Corporate Spies

-Unethical Employees

-Cyberextortionists

-Cyberterrorists

Internet and Network Attacks

An online security service is a Web site that evaluates your computer to check for Internet and e-mail vulnerabilities.

• Computer virus - Affects a computer negatively by altering the way the computer works.
• Worm - Copies itself repeatedly, using up resources and possibly shutting down the computer or network.
• Trojan Horse - A malicious program that hides within or looks like a legitimate program.
• Rootkit - Program that hides in a computer and allows someone from a remote location to take full control.

An infected computer has one or more of the following symptoms: 

• Operating system runs much slower than usual
• Available memory is less than expected
• Files become corrupted
• Screen displays unusual message or image
• Music or unusual sound plays randomly
• Existing programs and files disappear
• Programs or files do not work properly
• Unknown programs or files mysteriously appear
• System properties change
• Operating system does not start up
• Operating system shuts down unexpected
• -A botnet is a group of compromised computers connected to a network. A compromised computer is known as a zombie.

-A back door is a program or set of instructions in a program that allow users to bypass security controls.

-Spoofing is a technique intruders use to make their network or Internet transmission appear legitimate

-A firewall is hardware and/or software that protects a network's resources from intrusion.

-Intrusion detection software

• Analyzes all network traffic
• Assesses system vulnerabilities
• Identifies any unauthorized intrusions
• Notifies network administrators of suspicious behavior patterns or system breaches
• -Honeypot
•   Vulnerable computer that is set up to entice an intruder to break into it

Unauthorized Access and Use

Unauthorized access is the use of a computer or network without permission.
Unauthorized use is the use of a computer or its data for unapproved or possibly illegal activities.

-Access controls define who can access a computer, when they can access it, and what actions they can take.

• Two-phase processes called identification and authentication
• User name
• Password
• Passphrase
• CAPTCHA

A possessed object is any item that you must carry to gain access to a computer or computer facility.

-Often are used in combination with a personal identification number (PIN)

A biometric device authenticates a person’s identity by translating a personal characteristic into a digital code that is compared with a digital code in a computer

Digital forensics is the discovery, collection, and analysis of evidence found on computers and networks

Many areas use digital forensics : 

• Law enforcement
• Criminal prosecutors
• Military intelligence
• Insurance agencies.

Hardware Theft and Vandalism
Hardware theft is the act of stealing computer equipment.
Hardware vandalism is the act of defacing or destroying computer equipment.

To help reduce the chances of theft, companies and schools use a variety of security measures : 

• Physical access controls
• Alarm systems
• Cables to lock equipment
• Real time location system
• Passwords, possessed objects, and biometrics

Software Theft

Software theft occurs when someone 

• Steals software media 
• Illegally copies a program 
• intentionally erases programs
• Illegally registers and/or activates a program

A single-user license agreement typically contains the following conditions: 

-Permitted to 

• Install the software on one computer
• Make one copy of the software
• Remove the software from your computer before giving it away or selling it. 

-Not permitted to

• Install the software on a network
• Give copies to friends or colleagues while continuing to use the software
• Export the software
• Rent or lease the software

Information Theft

Information theft occurs when someone steals personal or confidential information

Encryption is a process of converting readable data into unreadable characters to prevent unauthorized access.

A digital signature is an encrypted code that a person, Web site, or organization attaches to an electronic message to verify the identity of the sender.

-Popular security techniques include:

• Digital Certificates
• Transport Layer Security (TLS)
• Secure HTTP
• VPN

System Failure
A system failure is the prolonged malfunction of a computer.

A variety of factors can lead to system failure, including : 

• Aging hardware
• Natural disasters
• Electrical power problems.
• Errors in computers programs

Two ways to protect from system failures caused by electrical power variations include surge protectors and uninterruptable power supplies (UPS). 

Backing Up - The Ultimate Safeguard

A backup is a duplicate of a file, program, or disk that can be used if the original is lost, damaged, or destroyed. To back up a file means to make a copy of it

Offsite backups are stored in a location separate from the computer site.

Two categories of backup :

• Full backup 
• selective backup 

Wireless Security
In additional to using firewalls, some safeguards improve security of wireless networks: 

• A wireless access point should not broadcast an SSID
• Change the default SSID
•  Use WPA or WPA2 security standards.
• Configure a WAP so that only certain devices can access it 
• 
  

Ethics and Society

Computer ethics are the moral guidelines that govern the use of computers and information systems.

Intellectual property rights are the rights to which creators are entitled for their work. 

An IT code of conduct is a written guideline that helps determine whether a specific computer action is ethical or unethical.

Green computing involves reducing the electricity and environmental waste while using a computer.

Information privacy refers to the right of individuals and companies to deny or restrict the collection and use of information about them

A cookie is a small text file that a Web server stores on your computer. 

Websites using cookies for some reason: 

•  Allow for personalization 
• Target advertisements 
• Store users passwords.
• Assists with online shopping 
• Track how users visit a site

Spam is an unsolicited e-mail message or newsgroup posting.

E-mail filtering blocks e-mail messages from designated sources

Anti-spam programs attempt to remove spam before it reaches your inbox.

Phishing is a scam in which a perpetrator sends an official looking e-mail message that attempts to obtain your personal and financial information

Pharming is a scam where a perpetrator attempts to obtain your personal and financial information via spoofing

Social engineering is defined as gaining unauthorized access or obtaining confidential information by taking advantages of trust and naivety

Employee monitoring involves the use of computers to observe, record, and review an employee's use of a computer

Content filtering is the process of restricting access to certain material on the Web

Web filtering software restricts access to specified Web sites.

Computer Security Risks

A computer security risk is any event or action that could cause a loss of or damage to computer hardware, software, data, information, or processing capability.

A cybercrime is an online or Internet-based illegal act.

-Hackers

-Crackers

-Script Kiddies

-Corporate Spies

-Unethical Employees

-Cyberextortionists

-Cyberterrorists

Internet and Network Attacks

An online security service is a Web site that evaluates your computer to check for Internet and e-mail vulnerabilities.

• Computer virus - Affects a computer negatively by altering the way the computer works.
• Worm - Copies itself repeatedly, using up resources and possibly shutting down the computer or network.
• Trojan Horse - A malicious program that hides within or looks like a legitimate program.
• Rootkit - Program that hides in a computer and allows someone from a remote location to take full control.

An infected computer has one or more of the following symptoms: 

• Operating system runs much slower than usual
• Available memory is less than expected
• Files become corrupted
• Screen displays unusual message or image
• Music or unusual sound plays randomly
• Existing programs and files disappear
• Programs or files do not work properly
• Unknown programs or files mysteriously appear
• System properties change
• Operating system does not start up
• Operating system shuts down unexpected
• -A botnet is a group of compromised computers connected to a network. A compromised computer is known as a zombie.

-A back door is a program or set of instructions in a program that allow users to bypass security controls.

-Spoofing is a technique intruders use to make their network or Internet transmission appear legitimate

-A firewall is hardware and/or software that protects a network's resources from intrusion.

-Intrusion detection software

• Analyzes all network traffic
• Assesses system vulnerabilities
• Identifies any unauthorized intrusions
• Notifies network administrators of suspicious behavior patterns or system breaches
• -Honeypot
•   Vulnerable computer that is set up to entice an intruder to break into it

Unauthorized Access and Use

Unauthorized access is the use of a computer or network without permission.
Unauthorized use is the use of a computer or its data for unapproved or possibly illegal activities.

-Access controls define who can access a computer, when they can access it, and what actions they can take.

• Two-phase processes called identification and authentication
• User name
• Password
• Passphrase
• CAPTCHA

A possessed object is any item that you must carry to gain access to a computer or computer facility.

-Often are used in combination with a personal identification number (PIN)

A biometric device authenticates a person’s identity by translating a personal characteristic into a digital code that is compared with a digital code in a computer

Digital forensics is the discovery, collection, and analysis of evidence found on computers and networks

Many areas use digital forensics : 

• Law enforcement
• Criminal prosecutors
• Military intelligence
• Insurance agencies.

Hardware Theft and Vandalism
Hardware theft is the act of stealing computer equipment.
Hardware vandalism is the act of defacing or destroying computer equipment.

To help reduce the chances of theft, companies and schools use a variety of security measures : 

• Physical access controls
• Alarm systems
• Cables to lock equipment
• Real time location system
• Passwords, possessed objects, and biometrics

Software Theft

Software theft occurs when someone 

• Steals software media 
• Illegally copies a program 
• intentionally erases programs
• Illegally registers and/or activates a program

A single-user license agreement typically contains the following conditions: 

-Permitted to 

• Install the software on one computer
• Make one copy of the software
• Remove the software from your computer before giving it away or selling it. 

-Not permitted to

• Install the software on a network
• Give copies to friends or colleagues while continuing to use the software
• Export the software
• Rent or lease the software

Information Theft

Information theft occurs when someone steals personal or confidential information

Encryption is a process of converting readable data into unreadable characters to prevent unauthorized access.

A digital signature is an encrypted code that a person, Web site, or organization attaches to an electronic message to verify the identity of the sender.

-Popular security techniques include:

• Digital Certificates
• Transport Layer Security (TLS)
• Secure HTTP
• VPN

System Failure
A system failure is the prolonged malfunction of a computer.

A variety of factors can lead to system failure, including : 

• Aging hardware
• Natural disasters
• Electrical power problems.
• Errors in computers programs

Two ways to protect from system failures caused by electrical power variations include surge protectors and uninterruptable power supplies (UPS). 

Backing Up - The Ultimate Safeguard

A backup is a duplicate of a file, program, or disk that can be used if the original is lost, damaged, or destroyed. To back up a file means to make a copy of it

Offsite backups are stored in a location separate from the computer site.

Two categories of backup :

• Full backup 
• selective backup 

Wireless Security
In additional to using firewalls, some safeguards improve security of wireless networks: 

• A wireless access point should not broadcast an SSID
• Change the default SSID
•  Use WPA or WPA2 security standards.
• Configure a WAP so that only certain devices can access it 
• 
  

Ethics and Society

Computer ethics are the moral guidelines that govern the use of computers and information systems.

Intellectual property rights are the rights to which creators are entitled for their work. 

An IT code of conduct is a written guideline that helps determine whether a specific computer action is ethical or unethical.

Green computing involves reducing the electricity and environmental waste while using a computer.

Information privacy refers to the right of individuals and companies to deny or restrict the collection and use of information about them

A cookie is a small text file that a Web server stores on your computer. 

Websites using cookies for some reason: 

•  Allow for personalization 
• Target advertisements 
• Store users passwords.
• Assists with online shopping 
• Track how users visit a site

Spam is an unsolicited e-mail message or newsgroup posting.

E-mail filtering blocks e-mail messages from designated sources

Anti-spam programs attempt to remove spam before it reaches your inbox.

Phishing is a scam in which a perpetrator sends an official looking e-mail message that attempts to obtain your personal and financial information

Pharming is a scam where a perpetrator attempts to obtain your personal and financial information via spoofing

Social engineering is defined as gaining unauthorized access or obtaining confidential information by taking advantages of trust and naivety

Employee monitoring involves the use of computers to observe, record, and review an employee's use of a computer

Content filtering is the process of restricting access to certain material on the Web

Web filtering software restricts access to specified Web sites.

Chapter 10 : Managing a Database

Databases, Data, and Information

1. Database - Collection of data organised in a manner that allows access, retrieval, and use of that data.
2. Data - Collection of unprocessed items such as Text, Numbers, Images, Audio, Video
3. Information - Processed data, Documents, Audio, Images, Video
4. Database software, often called a database management system (DBMS), allows users to: Create a computerised database. Sort and retrieve data.

-Valuable information should have the following characteristics : 

• Accurate
• Verifiable
• Timely
• Organized
• Useful
• Accessible
• Cost-effective.

The Hierarchy of Data

A character is one byte - Numbers, letters, space, punctuation marks, or other symbols.

A field is a combination of one or more related characters. 

1. Field name 
2.  Field size 
3. Data type.

 Common data types include : 

• Text
• Numeric 
• Date 
• Memo 
• Object
• AutoNumber
• Currency

A record is a group of related fields 

-- primary key uniquely identifies each record

-A data file is a collection of related records.

Maintaining Data

File maintenance refers to the procedures that keep data current :

• Adding records 
• Modifying records  
• Deleting records.

Validation compares data with a set of rules or values to find out if the data is correct.

•Alphabetic/Numeric check

•Range check

•Consistency check

•Completeness check

•Check digit

•Other checks

File Processing Versus Databases
File processing system  

•  used for many years  
• have data redundancy 
• isolate data

Database approach 

•Programs and users share data

•Reduce data redundancy

•Improve data integrity

•Share data

•Allows easier access

•Reduces development time

•Can be more vulnerable

Database Management System

-A data dictionary contains data about each file in the database each field in those files.

-A DBMS provides tools allow users to retrieve and maintain data in the database 

• Query language
• Query by example
• Form
• Report generator.

A query language consists of simple, English-like statements that allow users to specify the data to display, print, or store.

Query by example (QBE) provides a GUI to assist users with retrieving data.

A form is a window on the screen that provides areas for entering or modifying data in a database

A report generator allows users to design a report on the screen, retrieve data into the report design, and then display or print the report.

A DBMS provides a variety of techniques to restore the database to a usable form in case it is damaged or destroyed such as :

• Backup
• Log 
• Recovery utility 
• Continuous backup.

Relational, Object-Oriented, and Multidimensional Databases

A data model consists of rules and standards that define how the database organizes data.

A relational database stores data in tables that consists of rows and columns. 

-Each row has a primary key

-Each column has a unique name.

A relationship is a link within the data.

An object-oriented database (OODB) stores data in objects.

Examples of applications appropriate for an object-oriented database include :

• multimedia database 
• Groupware database
• Hypertext database.

A multidimensional database can store data in more than two dimensions of data

• Sometimes known as a hypercube
• Can consolidate data much faster than a relational database

A data warehouse is a huge database that stores and manages the data required to analyze historical and current transactions.

Web Database

Databases on the Web allow you to: 

1. Check semester grades
2. Search for a job
3. Buy or sell stocks
4. Shop for products or services
5. Make airline reservations
6. Register for college classes.

Database Administration

Database analysts and administrators are responsible for managing and coordinating all database activities

Database Analyst (DA)

-Decides on proper field placement, defines data relationship, and identifies users’ access privileges

Database Administrator (DBA)

-Creates and maintains the data dictionary, manages security, monitors performance, and checks backup and recovery procedures

Chapter 9 : Networks and Communications

Communications

-Communications describes a process in which two or more computers or devices transfer data, instructions, and information. Sending device, Communications channel, Receiving device.

Uses of Computer Communications

-Users can send and receive wireless messages using wireless messaging services. Text messaging allows users to send message thru phone or other mobile devices. Picture messaging allows users to send pictures and sound files. Video messaging allows users to send short video clips.

-Wireless Internet access points allow people to connect wirelessly to the Internet from home, work, school, and in many public locations.

-A cyber cafe is a coffeehouse, restaurant, or other location that provides personal computers with Internet access to its customers.

-A global positioning system (GPS) is a navigation system that consists of one or more earth-based receivers that accept and analyze signals sent by satellites in order to determine the GPS receiver's geographic location.

-Groupware : helps groups of people work together on projects and share information over a network. Major feature is group scheduling.

-Voice mail : allows someone  to leave a voice message for one or more people. A voice mailbox is a storage location on a hard disk in the voice mail system.

Networks

-A network is a collection of computers and devices connected together via communications devices and transmission media. Advantages of a network include :Sharing hardware and software, Transferring funds, and Sharing data and information.

-A local area network (LAN) is a network that connects computers and devices in a limited geographical area

-A wireless LAN (WLAN) is a LAN that uses no physical wires.

-A wide are network (WAN) is a network that covers a large geographical area.

-A network topology refers to the layout of the computers and devices in a communications network.

-An intranet is an internal network that uses Internet technologies.

-An extranet allows customer or suppliers to access part of its intranet.

Network Communications Standards

-Ethernet is a network standard that specifies no computer controls when data can be transmitted. The token ring standard specifies that computers and devices on the network share or pass a special signal (token). TCIP/IP is a network standard that defines how messages are routed from one end of a network to another.

-Bluetooth defines how two Bluetooth devices use short-range radio waves to transmit data.

-WiMAX (802.16) : Developed by IEEE. Towers can cover a 30-mile radius. Provides wireless broadband Internet access.

-Wireless Application Protocol (WAP) : Specifies how some mobile devices can display the content of Internet services. Uses a client/server network.

Communications Software

Communications software consists programs that : 

1. Help users establish a connection to another computer or network. 

2 .Manage the transmission of data, instructions, and information. 

3. Provide an interface for users to communicate with one another.

Communications Over the Telephone Network

-The public switched telephone network (PSTN) is the worldwide telephone system.

-ADSL connections transmit data downstream at a much faster rate than upstream.

Communications Devices

A communications device is any type of hardware capable of transmitting data, instructions, and information between a sending deice and a receiving device.

-A digital modem sends and receives data and information to and from a digital line such as DSL modem and Cable modem.

-A wireless modem uses the cell phone network to connect to the Internet wirelessly from a notebook computer, a smart phone, or other mobile device. 

-A network card enables a computer or device to access a network.

Home Networks

Home networks provide computers with the following capabilities : 

-Connect to the Internet at the same time

-Play multiplayer games

-Connect game consoles to the Internet.

Types of wired home networks : 

-Ethernet

-Powerline cable 

-Phoneline.

Wireless Transmission Media

Cellular radio is a form of broadcast radio that its used widely for mobile communications

Microwaves are radio waves that provide a high-speed signal transmission

A communications satellite is a space station that receives microwaves signals from an earth-based station, amplifies it, and broadcasts the signal over a wide area.

Chapter 8 type of storage

Storage

Storage holds data, instructions, and information for future use. A storage medium is the physical material on which a computer keeps data, instructions, and information.

-Capacity is the number of  bytes a storage medium can hold.

-A storage device is the computer hardware that records and/or retrieves items to and from storage media. 

-Reading is the process of transferring items from a storage medium into memory. 

-Writing is the process of transferring items from memory to a storage medium.

Hard Disks

A hard disk contains one or more inflexible, circular platters that use magnetic particles to store data, instructions, and information.

Characteristics of hard disk :

•Capacity

•Platters

•Read/Write Heads

•Cylinders

•Sectors and Tracks

•Revolutions per Minute

•Transfer Rate

•Access Time

-Formatting is the process of dividing the disk into tracks and sectors so that the operating system can store and locate data and information on the disk.

-RAID (redundant array of independent disks) is a group of two or more integrated hard disks

-A network attached storage (NAS) device is a server connected to a network with the sole purpose of providing storage

Flash Memory Storage

Flash memory chips are a type of solid state media and contain no moving parts.

- memory card is a removable flash memory device that you insert and remove from a slot in a computer, mobile device, or card reader.

- USB flash drives plug into a USB port on a computer or mobile device.

Cloud Storage

Cloud storage is an Internet service that provides storage to computer users for variety of reasons such as : Access file from any computer, Store large files instantaneously, Allow others to access their files.

Optical Discs

An optical disc consists of a flat, round, portable disc made of metal, plastic, and lacquer that is written and read by a laser.

Other types of storage

-Tape is a magnetically coated ribbon of plastic capable of storing large amounts of data and information.

-A tape drive reads and writes data and information on a tape.

-A magnetic stripe card contains a magnetic stripe that stores information.

-A smart card stores data on a  thin microprocessor embedded in the card.

-Microfilm and microfiche store microscopic images of documents on a roll or sheet film.

Chapter 7 understanding output

What is Output

-Output is data that has been processed into a useful form.

-An output device is any type of hardware component that conveys information to one or more people.

Display Devices

-A display device visually conveys text. graphics, and video information 

-A monitor is packaged as a separate peripheral.

Liquid crystal display (LCD) uses a liquid compound to present information on a display device.The quality of an LCD monitor or LCD screen depends primarily on

-Resolution 

-Response time

-Brightness 

-Dot pitch

-Contrast ratio

Resolution is the number of horizontal and vertical pixels in a display device.

Plasma monitors are display devices that use gas plasma technology and offer screen sizes up to 150 inches.

HDTV is the most advanced form of digital television.

A CRT monitor is a desktop monitor that contains a cathode-ray tube.

Printers

A printer produces text and graphic on a physical medium.

-A non-impact printer forms characters and graphics on a piece of paper without actually striking the paper.

-An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper.

-A multi-function peripheral (MFP) is a single device that prints, scans, copies, and in some cases, faxes.

-A thermal printer generates images by pushing electrically heated pins against the heat-sensitive paper.

-A mobile printer is a small, lightweight, battery-powered printer that allows a mobile user to print from a, notebook computer, smart phone, or other mobile device.

-A label printer is a small printer that prints on adhesive-type material

-Plotters used to produce high-quality drawings

-Large-format printers create photo-realistic quality color prints on larger scale

Speakers, Headphones, and Earbuds

An audio output device produces music, speech, or other sounds.

-Headphones are speakers that cover of the ear.

-Earbuds (also called earphones) rest inside the ear canal.

Other Output Devices

An interactive whiteboard is a touch-sensitive device, resembling a dry-erase board, that displays the image on a connected computer screen.

Chapter 6 Understand Input

What is Input?

-Input is any data instructions entered into the memory of a computer.Instructions can be entered into the computer in the form of programs, commands, and user responses.

-Input device is any hardware component that allows users to enter data and instructions into a computer.

The Keyboard

-an input device that contains keys users press to enter data and instructions into a computer.

-Most desktop computer keyboards have between 101 and 105 keys, function keys, CTRL keys, ALT keys, and arrow keys. A numeric keypad on the right side of the keyboard.

-The insertion point is a symbol on the screen that indicates where the next character you type will appear.

-An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries. Ergonomics incorporates comfort, efficiency, and safety into the design of the workplace.

Mouse

-A mouse is a pointing device that fits under your hand comfortably. A mouse can be wired or wireless.

Other Pointing Devices : Trackball ,Touchpad ,Pointing Stick 

Touch Screens and Touch-Sensitive Pads

-A touch screen is a touch-sensitive display device

Pen Input

With pen input, you touch stylus or digital pen on a flat surface to write, draw, or make selections.

Game Controllers

Video games and computer games uses a game controller as the input device that directs movements and actions of on-screen objects such as gamepads, joysticks and wheels, light guns, dance pads, and motion-sensing controllers.

Digital Cameras

A digital camera is a mobile device that allows users to take pictures and store them digitally. There are Studio cameras, Field cameras, and Point-and-shoot cameras.

Two factors affect the quality of digital camera photos : 

-Resolution - is the number of horizontal and vertical pixels in a display device. 

-Number of bits stored in each pixel - each pixel consists of one or more bits of data. The more bits used to represent a pixel, the more colors and shade of gray that can be represented.

Voice Input

-Voice input is the process of entering input by speaking into a microphone.

-Voice recognition is the computer's capability of distinguishing spoken words.

-Audio input is the process of entering any sound into the computer like : Speech, Music, Sound Effects.

Video Input

-Video Input is the process of capturing full-motion images and storing them on a computer's storage medium.

-A Web cam is a type of digital video camera that enables user to : Capture video and still images, Make video telephone calls, and add live images to instant messages.

-A video conference is a meeting between two or more geographically separated people.

Scanner and reading devices 

-Optical character recognition (OCR) involves reading characters from ordinary documents.

-A turnaround document is a document you return to the company that creates and sends it.

-A bar code reader, also called a bar code scanner users laser beams to read bar codes.

- Magnetic stripe card readers read the magnetic stripe on the back of cards such as : Credit cards, Entertainment cards, Bank cards, Other similar cards.

Biometric input 

-Biometrics authenticates a person’s identity by verifying a personal characteristic

-Fingerprint reader

-Face recognition system

-Hand geometry system

-Voice verification system

-Signature verification system

-Iris recognition system

-Retinal scanners

Chapter 5 type of utility programs nad operating systems

Chapter 5 : Type of utility Programs and operating systems 

System Software

System Software consists of 2 programs that control or maintain the operations of the computer and its devices.

1. Operating Systems - is a set of programs containing instructions that work together to coordinates all the activities among computer hardware resources.

Utility program - type of system software that allows a user to perform maintenance-type tasks

Operating System Functions

• The process of starting or restarting a computer is called booting.Cold boot is turning on a computer that has been powered off completely.
• Warm boot is using the operating system to restart a computer.

A boot drive is the drive from which your computer starts.You can boot from a boot disk.A recovery disk contains a few system files that will start the computer.

• Sleep mode saves any open documents and programs to RAM, turns off all unneeded functions, 

and then places the computer in a low-power state

• Hibernate saves any open documents and programs to a hard disk before removing power from 

the computer 

User interface controls how you enter data and instructions and how information is 

displayed on the screen .A command-line interface, a user uses the keyboard to enter data 

and instructions. 

How an operating system handles programs directly affects your productivity .

-single user and multiuser 

- single tasking and multi tasking 

- fore background and background 

-Preemptive multitasking 

-Multi processing 

Memory management optimises the use of RAM.Virtual memory is a portion of a storage 

medium functioning as a additional RAM.

A driver is a small program that tells the operating system how to communicate with a 

specific device. Plug and Play automatically configures new devices as you install them.

Operating systems typically provide a means to establish Internet connections

A performance monitor is a program that assesses and reports information about various 

computer resources and devices.

Operating systems often provide users with the capability of : 

-managing files 

-uninstalling programs

-searching for files 

-cleaning up disks 

-backing up files and disks

-viewing images

-defragmenting disks

-setting up screen savers 

-securing a computer 

-diagnosing problems

Automatic update - automatically provides updates to the program

Server operating system - organises and coordinates how multiple users access and share 

resources on a network.

Type of Operating system 

-Stand-alone 

-Server

-embedded 

Stand-alone Operating system 

A stand-alone operating system is a complete operating system that works on a desktop 

computer, notebook computer, or mobile computing device . 

Windows 7 is a Microsoft's fastest, most efficient operating system to date and is available 

in multiple editions: 

-Windows 7 Starter 

-Windows 7 Home Premium

-Windows 7 Ultimate 

-Windows 7 Professional

Macintosh operating system has set the standard for operating system ease of use. 

Latest version is Mac OS X.

UNIX is a multitasking operating system developed in the early 1970s.

Linux is an open-source popular, multitasking UNIX-type operating system.

Server Operating systems

-Windows server 2008 

-UNIX

-Linux

-Solaris 

-Netware

Windows Server 2008 is an upgraded Windows Server of 2003

Embedded Operating system

Embedded operating system -resides on a ROM chip on a mobile device or consumer 

electronic device.

Utility Programs 

-is a type of system software that allows a user to perform maintenance-type tasks

File manager - is a utility that performs functions related to file management 

For example:

-Displaying a list of files

-Organising files in folder

-Copying, renaming, deleting, moving, and sorting files and folders 

-Creating shortcuts 

A search utility is a program that attempts to locate a file on your computer based on 

criteria you specify.

An image viewer allows users to display, copy, and print the contents of a graphic file.

An uninstaller removes a program, as well as any associated entries in the system files.

A disk cleanup utility searches for and removes unnecessary files.

A disk defragmenter reorganizes the files and unused space on a computer's hard disk so 

that the operating system accesses data more quickly and programs run faster.

A backup utility allows users to copy files to another storage.

A restore utility reverses the process and returns backed up files to their original form.

Screen saver causes a display of a moving image if no activity occurs for a specified time.

Personal firewall detects and protects a personal computer from unauthorized intruders.

A virus damage the computer program and affects the computer potentially. 

A worm copies itself repeatedly in memory or over a network. 

A Trojan horse hides within or looks like legitimate program. 

An antivirus program protects a computer against viruses.

Spyware is a program placed on a computer without the user's knowledge that secretly 

collects information about the user.

Spyware remover detects and delete spyware and other similar programs.

Adware displays an online advertisement in a banner or pop-up window. 

An adware remover is a program that detects and deletes adware.

Chapter 4

Chapter 4 : System Unit Components 

System unit is a case that contains electronic components of the computer used to process data .

Inside system unit have :

1. Drive bay
2. Power supply 
3. Sound card 
4. Video card 
5. Processor 
6. Memory 

Motherboard - Main circuit board of the system unit

Processor 

Processor also known as Central Processing Unit (CPU), interprets and carries out the basic instructions that operate a computer and contain a control unit and an arithmetic logic unit(ALU)

Have 3 different processor : Multicore processor , Dual-core processor ,  Quad-core Processor 

Control units - is a components of the processor that directs and coordinates most of the operations in the computer

Arithmetic logic unit (ALU) - Performs arithmetic , comparison , and  other  operations

Systems clock - Controls the timing of all computer operations . The pace of the systems clock is called the clock speed , and is measured in gigahertz

A processor chips generates heat that could cause the chips burn up so require a cooling systems to cool it down like Heat sinks and Liquid cooling technology .

Data representation 

Analog - signals are continuous and vary in strength and quality

Digital -  signals are in one of two states : on or off

The Binary system uses two unique digits (0 and 1)

ASCII(American standard Code For Information Interchange) is the most widely used coding scheme to represent data

How a letter is converted to binary  form and back 

• Step 1 : Press 'T' (Shift + T keys ) on the keyboard which in turn creates a special code , called scan code .
• Step 2 : The scan code for the capital letter T is sent to the system units
• Step 3 : The system unit converts the scan code for the capital letter T to its ASCII Binary code  and stores its in its memory for processing.
• Step 4 : After processing , the binary code for the capital letter T is converted to an image and display on the output 

Memory

Memory consists of electronic components that stores instructions waiting to be executed by processor ,data needed by those instructions . 

Memory size is measured in kilobytes(K) , megabytes (MB) , gigabytes (GB) , terabytes (TB)

The system unit contains two types of memory 

Volatile memory - contains will lose when power off 

Non-volatile memory - contains will not lose when power off

Three basics type of RAM

1. Dynamic RAM(DRAM)
2. Static RAM (SRAM)
3. Magnetoresistive RAM(MRAM)

RAM chips is locate on a memory module and inserted into memory slots .The amount of RAM is important and its depends on types of software you using 

Memory cache - speeds the processes of the computer because it stores frequently used instructions and data 

Flash memory - can be erased and rewritten 

Expansion slots and Adapter cards

Expansion slots is a sockets on the mother board that can hold an adapter card 

Adapter card enhances functions of a component or provides connections to peripherals like sounds card and Video card

Removable flash memory - Memory cards , USB Flash drives , and PC Cards 

Port and Connectors 

Port - peripheral attaches to or communicates with a system unit