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2. Bit, nibble and byte


A single bit is the smallest size of digital data and has only two values - zero and one.

a single bit
Roll over the image to see the two types of binary bits

The symbol for a bit is a lowercase "b". So "sixteen bits" would be written as 16 b.


A 'byte' contains 8 bits, for example 11101001 is a byte.

A single keyboard character that you type, such as the letter A or the letter T takes up one byte of storage.

letter A in binary
Roll over the image to see the letter A in binary format (ascii code)

The symbol for a byte is an uppercase "B". Sixteen bytes is written as 16 B.


This is not a very commonly used term compared to bit and byte. It is the term given to a group of four bits. Therefore two nibbles make a byte.

The reason it is not very common is because most microprocessors use groups of 8 bits and higher i.e. They use one or more bytes to process data. Not many devices make use of a nibble, and there is no universally agreed-upon symbol for it.


Challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: Binary digit