Computers represent all data using bits, binary digits with one of two possible values, or . Bits are grouped into bytes, usually eight bits, and interpreted through agreed encoding systems to represent numbers, text, images, sound and other forms of data.
A single bit has two possible states. With bits, a computer can represent different patterns. Therefore, one byte can represent patterns, ranging from 00000000 to 11111111.
The bit pattern has no inherent meaning. Its meaning depends on the encoding used by the digital system. For example, under ASCII encoding, 01000001 represents the uppercase letter A. The same pattern could represent a numerical value or part of a pixel under a different encoding system.
| Data type | How bits and bytes represent it |
|---|---|
| Numbers | Binary place values represent quantities. For example, 00000101 represents . |
| Text | Character encodings such as ASCII or Unicode assign bit patterns to letters, symbols and characters. |
| Images | Pixels are represented by numerical values for properties such as red, green and blue intensity. |
| Sound | Samples of an analogue sound wave are converted into numerical values stored as binary data. |
This connects directly to IB Digital Society area for inquiry 1.1D, which states that digital systems use binary digits to represent data and information. It also supports the distinction between data and information: bits store raw data, while that data becomes information when it is interpreted in context. A common misconception is that binary patterns automatically carry meaning. They do not; an encoding system and context are required.
For both SL and HL exams, an explain response should give the mechanism, not merely define a bit. State that bits form patterns, bytes group bits, and encoding rules determine what those patterns represent. A short example such as 01000001 representing A provides effective development.
