Gigabyte

n. (Computers) one billion bytes; unit of information which equals 1,073,741,824 bytes or 1024 megabytes

A gigabyte or Gbyte (derived from the SI prefix giga-) is a unit of information or computer storage meaning either 1000³ bytes or 1024³ bytes (1000³ = one billion). The usage of the word "gigabyte" is ambiguous, depending on the context. When referring to RAM sizes and file sizes, it traditionally has a binary definition, of 1024³ bytes. For every other use, it means exactly 1000³ bytes. In order to address this confusion, currently all relevant standards bodies promote the use of the term "gibibyte" for the binary definition.
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Noun
1. a unit of information equal to one billion (1,073,741,824) bytes or 1024 megabytes
(synonym) G, GB
(hypernym) computer memory unit
(part-holonym) terabyte, T, TB
(part-meronym) megabyte, MB

n. giga byte, information storage unit equal to one billion bits (Computers)

n. Gigabyte, unit of information which equals one billion bytes (Computers)