General purpose computers
A general purpose computer is a computer that is designed to be able to carry out many different tasks. A PC is an example of a general purpose computer. Among other things, it can be used to:
- access the internet
- browse the world wide web
- use word processing software
- play games
- communicate via email and social media
- design and build web pages
- store and retrieve data
- play videos and music
Each of these tasks is called an application. Any computer that can have many applications, such as those listed, is a general purpose computer.
Apart from PCs and laptops, the following devices are also classed as general purpose computers:
- tablets - like PCs, they can run a variety of applications
- smartphones - today's smartphones can also run a variety of applications
- games consoles - as well as games, modern consoles also allow users to watch videos, play music and browse the internet
- media systems in cars - allow users to navigate, listen to music and connect to a smartphone
Hardware and software
General purpose computers consist of hardware and software. Hardware is the physical components of the computer, such as the central processing unit (CPU), hard disk, monitor, keyboard and mouse. Software is the programs that run on a computer.
Hardware is the physical components of a computer. Software is the programs that run on a computer.
The general purpose computer model
All general purpose computers follow the same basic model.
The diagram illustrates the flow of data within a computer. Data is input, processed and then either output or sent to secondary storage. It is held in primary memory while it is being processed.
The CPU receives instructions and data from an input or memory. The instructions and data are processed by the CPU and the results are either sent to an output or transferred to secondary storage.
Input is from an input device, such as a keyboard, mouse, camera or scanner. Output is to an output device, such as a monitor, printer or speaker.
THE CPU processes data/instructions and controls the computer system.
The purpose of the CPU
The CPU is the most important hardware component in a computer. It has two main functions:
- to process data and instructions
- to control the rest of the computer system
All programs and data processing are run in the CPU and all hardware components are, to some extent, controlled by it.