What is digital data?
Computers can only work with digital information. Everything that they process must first be turned into a digital signal in one of two states: ‘on’ or ‘off’.
At a basic level a computer processor is a collection of switches which can either be on or off. These switches are known as transistors. The computer processes information by switching transistors on and off automatically.
Information from input devices must be digitised so the information can be processed.
Why do computers use binary?
In order to process information and store it, computers use binary code. Binary is a language composed of just the numbers 1 and 0.
It is stored in switches (transistors) as either on or off, just like a digital signal.
It can be stored on a computer disk using tiny areas magnetically charged with north and south – a bit like you find on a bar magnet. One direction stands for 1, and the other direction stands for 0.
When we say data is ‘digitised’ we mean it is turned into 1s and 0s for storage.