Introduction to Computer Science

Computer Science Overview

• Computer science involves problem-solving
• A successful candidate should understand core ICT concepts, devices, and software
• Key skills involve starting, shutting down a computer, managing files, and understanding network concepts

Computer Science Disciplines

• Computer science disciplines include algorithms, data structures, computer and network design
• Further disciplines are modelling data and information processes and artificial intelligence

Computer Definition and Function

• A computer is an electronic device which accepts and processes data into useful information

Computer Functionality

• Input comprises information such as typed text or mouse clicks
• Processing consists of the operations the computer performs on the inputs
• Output provides visual, auditory, or tactile perceptions after processing, such as text, images, sound, or video

Computer Understanding

• An intermediary is needed between humans and computers to translate human languages into binary code
• Computers understand natural language, sounds, shapes, and symbols by default
• Languages and multimedia are understood through binary coding

Binary System

• The binary number system is how computers represent data
• Byte is a unit of digital information that most commonly consists of eight bits

Representing Languages

• Letters of languages are represented through binary

Representing Colour

• RGB has a different byte
• 3 bytes are required

Representing Picture

• Binary represents Pictures
• The hierarchy is as follows, pictures consist of pixels that consist of colours that consist of the RGB code that consist of a byte that consists of bits

Representing Videos

• Binary represents videos
• The hierarchy is videos consist of pictures that consist of pixels that consist of colours

Representing Audio

• Binary represents audio

Information and Communication Technology (ICT)

• ICT involves using digital technology to access, store, and process information so that it is organised
• IT and ICT stand for Information Technology, and Information and Communication Technology, respectively

ICT Services

• Examples of Internet services are online banking, online shopping, email and data processing

Other tasks using the Internet

• E-commerce involves buying/selling products through electronic systems
• E-government involves governments providing services to their citizens
• Teleworking, remote work involving benefits (easier, flexible) and disadvantages (less social)
• E-banking enables customers to perform a range of transactions, and access an appropriate network
• E-learning removes the need for learners to attend a physical classroom

Functions of a computer

• Lengthy calculations can now be completed within seconds
• Computers are easy to use and cost-effective
• Computers reduce manual labour
• Computers make storing information easier and convenient
• Years of data can be stored without fear of losing

Computer Components

• Computer systems are divided into hardware and software

Hardware

• Hardware refers to the physical components of a computer
• Examples of such pieces of computer hardware are the monitor, CPU, keyboard, and mouse

Software

• Software enables the hardware to perform specific tasks.
• Software must be installed in the hardware, and the hardware must be present for the software to function

Hardware vs Software

• Hardware is further divided into Input Devices, Output Devices, Secondary Storage Devices, Internal Components
• Software is divided into Application Software, System Software operating system
• When damaged hardware can be replaced, but damaged software can usually be reinstalled
• You can physically touch hardware but not software
• Hardware cannot be infected by viruses, but software can
• Hardware physically wears out, but software is affected by bugs

Computer output devices include:

-Keyboard -Mouse -Microphone -Touch Screen -Light Pen -Web Camera

Computer output devices include:

• Monitor -Printer -Speaker -CD -DVD

Computer storage devices include:

• Flash Memory -Optical Disk -Local Drives -Magnetic Tape -Magnetic Disk

Computer processing devices

• Mother Board -Processor -Random Access Memory -Read Only Memory -Switched Mode Power Supply

Types of computer software

• System software-OS -Application Software

System and Software Examples

• Windows -Linux -Mac OS -DOS

Application Software Examples

• Office productivity -Communications -Social networking -Media -Design -Mobile applications

Different Types of Software Licenses

• EULA-End User Licensed Agreement is a legal agreement between the user of software and the software company
• Proprietary is software that must be bought before use
• Open source is free software that makes the source code available
• Trial version is software that can be used for a limited time and users will have to purchase to use further
• Shareware is software that is distributed on a try-before-you-buy premise with limited functionality
• Freeware is free copyrighted software

Computer ports

• Serial port(COM port): Transmits data sequentially, one bit at a time
• Parallel Port(LPT ports): can send and receive 8 bits or 1 byte at a time
• Infrared Port: sends and receives infrared signals
• FireWire Port: is apple computer,s interface for high-speed communication
• USB (Universal Serial Bus): used to connect storage and devices
• High-definition multimedia interface(HDMI): used to connect media devices

Types of computer

• There are 4 of major computer types

Supercomputer

• These are computers which are used to process a large amount of data at once

Mainframe Computer

• These are computers that are used in large firms and organizations where a lot of people work with the same database

Workstation

• Used by a single-user system that has higher RAM and quite fast processors

Microcomputer

• Designed for personal use and is easily moved

Main types of devices include:

• Smartphones
• Desktop
• Laptop
• tablet -Smart Phone -Media Player -Digital Camera