4. Personal Computers

In the early days (1980s) these types of machine were called micro-computers, for example, schools often had a BBC micro-computer. But now we tend to call them 'desktop personal computers' or just 'PC'.

The desktop PC has a central processing unit housed in a metal or plastic case (often called a tower unit). A keyboard and mouse are usually used to input data and a monitor to output the data.

Until recently, most PCs all looked the same, a very boring beige or grey box. Now manufacturers are coming up with some really interesting designs such as the 'alien' design on the right.

Modern PCs are quite powerful. They can carry out millions of calculations per second.

They are useful for lots of different types of tasks:

• Running office applications such as word processors, spreadsheets and databases
• For CAD design such as designing kitchens
• Editing videos
• Creating and playing music
• Accessing the Internet for research, work and entertainment