Giga-

Giga (/ˈdʒɪɡə/ or /ˈɡɪɡə/) is a unit prefix in the metric system denoting a factor of a (short-form) billion (10⁹ or 1000000000). It has the symbol G.

Giga is derived from the Greek word γίγας, meaning "". The Oxford English Dictionary reports the earliest written use of giga in this sense to be in the Reports of the IUPAC 14th Conference in 1947: "The following prefixes to abbreviations for the names of units should be used: G giga 10⁹×".

When referring to information units in computing, such as gigabyte, giga may sometimes mean 1073741824 (2³⁰), although such use is inconsistent, contrary to standards and has been discouraged by the standards organizations. The inconsistency is that gigabit is never (or very rarely) used with the binary interpretation of the prefix, while gigabyte is sometimes used this way. The binary prefix gibi has been adopted for 2³⁰, while reserving giga exclusively for the metric definition.

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