Unit 7. Evolution of computers
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Computer Hardware Basics
– any physical device or equipment used in or with a computer system [anything you can see and touch].
External hardware
- – any hardware device that is located outside the computer.
- – a piece of hardware device which is used to enter information to a computer for processing.
- Examples: keyboard, mouse, trackpad [or touchpad], touchscreen, joystick, microphone, light pen, webcam, speech input, etc.
- – a piece of hardware device that receives information from a computer.
- Examples: monitor, printer, scanner, speaker, display screen [tablet, smartphone …], projector, head phone, etc.
Internal hardware
- – any piece of hardware device that is located inside the computer.
- Examples: CPU, hard disk drive, ROM, RAM, etc.
Computer Software Basics
Computer software
- – a set of instructions or programs that tells a computer what to do or how to perform a specific task [computer software runs on hardware].
- Main types of software – systems software and application software.
Application software
- – a computer program that provides users with tools to accomplish a specific task.
- Examples of application software: word processing, spreadsheets, presentation, database management, Internet browsers, email programs, media players, accounting, pronunciation, translation, desktop publishing, enterprise, etc.
System Software
– it is designed to run a computer’s hardware and application software, and make the computer system
available for use. It serves as the interface between hardware, application software, and the user.
- Main functions of system software – allocating system resources, managing storage space, storing and retrieval of files, providing security, etc.
- Main types of systems software – operating system, device driver, utility software, programming software, etc.
– a software that controls and coordinates the computer hardware devices and runs other software and applications on a computer. It is the main part of system software and a computer will not function without it.
- Main functions of an operating system – booting the computer, managing system resources [CPU, memory, storage devices, printer, etc.], managing files, handling input and output, executing and providing services for application software, etc.
- Examples of operating system: Microsoft Windows, Apple iOS, Android OS, macOS, Linux, etc.
– a software program that is designed to control a particular hardware device that is attached to a computer.
- The main purpose of device driver – it acts as a translator between the hardware device and operating systems or applications that use it.
- It instructs computer on how to communicate with the device by translating the operating system’s instructions into a language that a device can understand in order to perform the necessary task.
- Examples of device driver: printer driver, display driver, USB driver, sound card driver, motherboard driver, ROM driver, etc.
– a type of system software that helps set up, analyze, configure, strengthen, maintain a computer and performs a very specific task [e.g. antivirus software, backup software, memory tester, screen saver, etc.].
Quick revise
A computer is an information processing machine. Computers process data to produce information.
The sets of instructions that humans give computers are called programs or software.
Software that carries out a particular type of task for a user is often called applications software.
There are many reasons for using computers:
- Computers can work much faster than humans;
- Computers never get tired or need a rest;
- Computers can do jobs that it would be dangerous for a human to do;
- Computers can store large amounts of information in a very small space;
- Computers can find information very quickly;
- Computers never lose or misplace information.
The three stages of computing are input, processing and output.
A computer works through these stages by ‘running’ a program. A program is a set of step-by-step instructions which tells the computer exactly what to do with input in order to produce the required output.
Input
- This stage of computing is concerned with getting the data needed by the program into the computer.
- Input devices are used to do this.
- The most commonly used input devices are the mouse and the keyboard.
Processing
- The instructions about what to do with the input are contained in a program.
- During the processing stage the computer follows these instructions using the data which has just been input.
- What the computer produces at the end of this stage is called output.
Output
- This stage of computing is concerned with producing the processed data as information in a form that is useful to the user.
- Output devices are used to do this.
- The most commonly used output devices are the screen, which is also called a monitor or visual display unit [VDU] and the printer.
Data & Information
- Data is any collection of numbers, characters or other symbols that has been coded into a format that can be input into a computer and processed.
- Data on its own has no meaning, or context.
- It is only after processing by a computer that data takes on a context and becomes information.
- There are many types of data
- All data ends up being stored as a series of numbers inside the computer.
- Data can be input to the computer by the user in many different ways.
- The main types of data that can be input into a computer and processed are numeric, text, dates, graphics and sound.
Computer Systems
- Hardware is the name that is given to any part of a computer that you can actually touch.
- An individual piece of hardware is called a device.
- The basic hardware of any computer consists of a central processing unit [CPU] along with input, output and backing storage devices.
The central processing unit [CPU]
- This is the part of the computer where the searching and sorting of data, calculating and decision-making goes on.
- The CPU contains the Main Memory, the Control Unit and the Arithmetic and Logic Unit [ALU].
An introduction to processors
This video provides an explanation of the parts within a processor and the functions of each part. The Central Processing Unit contains the Arithmetic Logic Unit, which carries out all arithmetic operations plus AND/OR functions, and the Control Unit, where decisions are made about collecting and sending data.