AIS 3

Chapter 1 & 2

Information Technology

is the technology involving the development, maintenance, and use of computer systems, software, and networks for the processing and distribution of data.

1. hardware

2. software

3. data

4. networks

Components of Information Technology

software

the programs and other operating information used by a computer.

Hardware

The physical components of a computer.

Data

Is a collection of raw facts, numbers, words, or measurements. Without context, it has no meaning.

Networks

Is a group of connected devices that share data and tools. It links computers, phones, and printers using wires or wireless signals

Information System

is an interconnected set of components used to collect, store, process and transmit data and digital information. 

1. hardware

2. software

3. data

4. networks

5. process

6. people

Components of Information System

Bala and Henderson

Use of Internet to access remote hosts, data storage, and other IT capabilities from

the “The Cloud”

Software-as-a-Service (SaaS) 

third-party service providers deploy, manage, and remotely host software applications on a rental or lease agreement

Telecommuters

Individuals who work at home and communicate through portable computers, other mobile equipment, and emails that give them access to company data anytime with an Internet connection.

Virtual Teams

teams with members who are separated too far geographically to work face-to-face

Free Agents

Individuals with specialized skills who contract out their services without being a permanent employee of any organization.

Enterprise Systems

Software packages with integrated modules that pass common business transactions across groups, divisions, and geographic locations in “real-time”

Bandwidth

the maximum amount of data that can travel through a network connection in a set time

Information Systems (IS) Department

The organizational unit or department that has the primary responsibility for managing

IT.

Support Mode

focuses primarily on maintaining, stabilizing, and running existing technology infrastructure rather than driving strategic business transformation. [1]

Strategic Mode

treats technology as a core driver of business value and competitive advantage rather than a mere back-office support utility

Technology Infrastructure

Computer, software, and networks that enable an organization to conduct business and share information across organizational units as well as business partners

Human Resources

IT professionals and managers who have the needed mix of technology, business, and interpersonal skills to plan for, design, and manage the other IT resources

Business/ IT Relationships

Established relationships between business and IT workers to ensure that the other IT resources are aligned with business needs

Computer Systems

consists of hardware and software, which are used to capture, manipulate, communicate, and present data.

• Input

• Output

• Memory

• Arithmetic/logical unit

• Control unit

• Files

Basic Components of Computer Systems

INPUT DEVICES

are used to enter data and instructions into the computer for processing. The most commonly used are keyboard and mouse.

terminal

is a simpler device than a PC; it is designed strictly for input/output and does not incorporate a processor (CPU), and are connected to a central computer through a network and are commonly used in businesses for online transactions, such as point-of-sale (POS) terminals in retail stores and automated teller machines (ATMs) in banks.

Voice Input

which is done through speech recognition software allows users with limited typing skills, disabilities, repetitive stress injuries from overusing a computer keyboard to dictate or command texts.

Magnetic Ink Character Recognition (MICR)

is used by banks to read the special magnetic ink printed on checks.

Optical Character Recognition (OCR)

scans printed or handwritten text and converts it into digital data.

Imaging Scanners

digitize entire documents, photographs, charts, and forms so they can be stored, viewed, printed, or shared from a computer to another computer.

Bar Code Label

quickly and accurately read barcodes on products, making them widely used in supermarkets, retail stores, inventory management, healthcare, and attendance systems.

Output devices

present the processed information in a form that users can understand. the most common type of are the:

Video display units

Printers

CD and DVD drives

Computer Output Microfilm (COM)

- store large amounts of information on microfilm for long-term storage.

Voice Response Units (VRUs)

provide spoken computer-generated responses, commonly used in automated telephone systems.

Computer memory

also called main memory or primary memory, is the central storage area of a computer system.

operates on a principle of destructive read-in and non-destructive read-out

Destructive read-in

reading data from a memory cell inherently erases or alters its contents.

Non-destructive read-out

when data is retrieved from memory, it remains stored until it is replaced

byte

A memory cell that can store only one character of data

EBCDIC (Extended Binary Coded Decimal Interchange Code)

- developed by IBM in the 1950s, and is mainly used in mainframe systems.

ASCII (American Standard Code for Information Interchange)

widely used in personal computers and data communication.

Arithmetic Logic Unit (ALU)

is the part of the CPU responsible for performing arithmetic and logical operations. This receives data from memory, performs the required calculations or comparisons, and then sends the results back to memory for storage or further processing.

Secondary storage

allows computers to store large amounts of data at a lower cost than main memory. Data can be transferred from memory to storage for saving and from storage back to memory when needed for processing. 

Sequential Access Files

store the files or records in sequence or order based on a file’s control key. For example, a payroll record for each employee based on their ID number.

Direct Access File

which allows the computer to retrieve a specific record immediately without searching through the entire file.

Control Unit (CU)

acts as the central coordinator of the computer. It controls and manages the activities of all the major components, ensuring they work together properly.

Stored-Program Concept

is the fundamental principle behind modern computers. It states that both program instructions and data are stored in the computer's memory. A program is a sequence of instructions that tells the computer

it continuously follows the fetch–decode–execute cycle

program

is a sequence of instructions that tells the computer what to do.

Fetch

- The processor retrieves the next instruction from memory.

Decode

- The processor determines what the instruction means.

Execute

- The processor performs the required operation.

• Microcomputers

• Midrange Systems

• Mainframe Computers

• Supercomputers

TYPES OF COMPUTER SYSTEM

Microcomputers

also known as personal computers (PCs), are the most common and affordable type of computer system. They are designed for individual users, are portable, and generally cost less than larger computer systems.

Midrange System

are more powerful than microcomputers but less powerful than mainframes. They are designed to support multiple users and are commonly used as servers in businesses and organizations

Mainframe Computers

are large, powerful computer systems used by major corporations and government agencies to process massive amounts of data and support many users simultaneously.

are known for their high processing power, reliability, security, and availability, making them ideal for mission-critical operations that require continuous performance.

Supercomputers

are the most powerful and fastest type of computer systems, designed to perform extremely complex calculations and process massive amounts of data.

use thousands of processors working together, allowing them to perform millions to quadrillions of calculations per second. It also provides exceptional

processing speed through parallel processing, enabling the analysis of massive amounts of data in a very short time

COBOL (Common Business-Oriented Language)

eleased on 1959, by committee influenced by Dr. Grace Hopper

used primarily for legacy business infrastructure (business, finance, mainframes)

used by: Global ATM transactions, IRS Tax Processing System

C++

eleased in 1958, by Bjarne Stroustrup

provides raw hardware control (systems, games, and high-performance programs)

industry standard for performance-critical software

used by: Google Chrome, Microsoft Windows, Adobe Suit, Unreal Engine

Java

developed by James Gosling

used for cross-platform portability (enterprise apps, Android, Web Backends)

used by Minecraft, Android OS, Netflix

APPLICATIONS SOFTWARE

Includes all programs written to accomplish particular task for computer users.

SUPPORT SOFTWARE

also called systems software

Provides a computing environment in which it is relatively easy and efficient for humans to work. It also ensures that the hardware and software resources are efficiently used

SOFTWARE PACKAGE

are types of commercial products that are available for purchase. They are a bundle of related computer programs, file, documentation sold, downloaded, or subscribed all together

Operating System (OS)

is a very complex program that controls the operation of the computer hardware

and coordinates all the other software, so as to get as much work done as possible with the available resources.

Hypertext Markup Language (HTML)

is the standard markup language used to create and structure content on the World Wide Web.

eXtensible Markup Language (XML)

is a flexible text format used to store and send data between different computer systems. It lets users make their own tags to describe information, making it easy for both people and machines to read

Direct Access Storage Devices (DASDs)

 a digital storage unit where each physical record has a unique address for random data access