Data Units
- bit
- binary digit
- byte
- 8 bits
- in some situations 4 bits (half a byte) is called a nibble
- word
- single entity of one or more bytes
- size usually related to processor register width
- block
- single entity of many bytes used for mass storage reads and writes
- size usually from 512 to 4096 bytes
- prefixes (multipliers)
| name |
SI symbol |
SI value |
IEC symbol |
IEC value |
| Kilo |
K |
103 |
Ki |
210 |
| Mega |
M |
106 |
Mi |
220 |
| Giga |
G |
109 |
Gi |
230 |
| Tera |
T |
1012 |
Ti |
240 |
| Peta |
P |
1015 |
Pi |
250 |
| Exa |
E |
1018 |
Ei |
260 |
- common prefix usage
- storage: SI (decimal) in bytes, not including file system overhead
- memory: IEC (binary) in bytes
- networks: IEC (binary) in bits, not including communication overhead