Units of Capacity
Computer Science: OCR GCSE, topic 1.2.6
Units of Capacity
The capacity of a device is how much data it can store. It is important to know the units of capacity so that we can compare the capacity of different devices.
The bit
- The smallest unit of data that we can store is called a binary digit, or a bit for short.
- The value of a bit can be either a 0 or a 1.
Grouping bits
- Because a bit is so small, we do not usually use it to measure data.
- Instead, we group bits into larger groups such as:
- Nibble (4 bits).
- Byte (8 bits).
Common data units
- In reality, we need much larger groups than this to compare modern storage devices.
- Common units are:
- Kilobyte (KB) (1000 bytes).
- Megabyte (MB) (1000 KB).
- Gigabyte (GB) (1000 MB).
- Terabyte (TB) (1000 GB).
- Petabyte (1,000 TB).
Test yourself on Units of Capacity
What is the name of the smallest unit of data that a computer can store?