1. What is a computer?

2. Objectives Know what a computer is used for
Understand the difference between hardware and software
Be able to give examples of different types of hardware and software

3. Computer systems
Computer systems are commonplace now in every part of our lives. But what, exactly, is a computer system?
Computers come in a huge variety of shapes, and sizes. You will be most familiar with Personal Computers (PCs) – the small computer on your desk, or the laptop in your bag.

4. Computer systems
However there are some computers that fill whole buildings and others that are small enough to fit in a slim mobile telephone. Whatever the size, all computers do the same thing…

5. A computer is…
…a device that stores and processes data according to a set of instructions.
In other words, a computer is a device that you feed data into and it does something with the data (processes it) based on some instructions (a ‘program’) that it has been given.

6. What is a computer?
A computer is, basically, a data processing system.
The huge room-sized 'mainframe' above and
the tiny mobile phone circuitboard below it
are both computers

7. Data processing Data (eg mouse clicks) goes IN
Information (word documents etc) comes OUT

8. It doesn’t matter what type of computer we are looking at, or what programs the computer is running, it always takes in data and does something with it in order to produce information.

9. For example
A spreadsheet running on a personal computer:

10. Or…
Or a game being played on a games console (these are computers too)...

11. Hardware & Software
A computer system is made up of hardware and software. Hardware is a general term for all the physical components that you can see and touch: the keyboard, the mouse, the monitor, the CPU..... Software refers to the programs that control the hardware.

12. Types of Software
There are two types of software: Systems Software - this is software that allows the hardware to run properly, and includes Windows, MacOS, Linux etc Applications Software - this refers to programs that allow the user to do specific tasks: word processing, spreadsheets, multimedia presentations etc.

13. Your task:
Read the link on the wiki. Read the powerpoint presentation. Complete your worksheet. Extension tasks are on the wiki page.