Edexcel IGCSE·Computer Science·IGCSE Computer Science

Data Representation

13 min read

Binary, denary and hexadecimal, units of storage, and representing text, images and sound.

Computers store all data in binary.

Number systems

Binary (base 2): place values

\dots 16, 8, 4, 2, 1

Hexadecimal (base 16): 0–9 then A–F; one hex digit = four bits.

Worked example. Binary $1011 = 8 + 2 + 1 = 11$ . Denary $25 = 11001$ . Hex $\text{FF} = 255$ .

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