For the Baroque dance, see gigue.

giga- (symbol: G) is a prefix in the SI system of units denoting 10⁹, or 1 000 000 000.

Confirmed in 1960, it comes from the Greek γίγας, meaning giant.

In computing, giga- can sometimes mean 1 073 741 824 (2³⁰) for information units, eg gigabit or gigabyte, but can also denote 1 000 000 000 of other quantities, e.g. transfer rates: 1 gigabit/s = 1 000 000 000 bit/s. The binary prefix gibi- has been suggested for 2³⁰, to resolve this ambiguity, but has yet to achieve widespread usage.

Pronunciation

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As giga is a greek word and greek is a phonetic language it is pronounced with a hard G as in giggle. An incorrect pronunciation is found in the 1985 movie Back to the Future, where gigawatts was pronounced as jigawatts. This was before units like gigabyte became common, and was used to emphasize magnitude, since quantities that large were rare at the time. This pronunciation was briefly popular in the USA before the correct hard G pronunciation came into common use as measurements such as gigabyte and gigahertz became ubiquitous.

Common usage

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• Gigabyte — hard disk capacity, e.g. 120 GB; DVD capacity, e.g. 4.7 GB = 4.7 × 1 073 741 824 bytes
• Gigahertz — clock rate of a CPU, e.g. 3 GHz = 3 000 000 000 Hz
• Gigabit — bandwidth of a network, e.g. 1 Gbit = 1 000 000 000 bit/s
• Gigabort - Common slang expression that could represent any of the above. Used to mock those that don't know the difference between bytes, bits, hertz, etc.

See also

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• SI prefix
• Binary prefix
• gibibyte
• Gigabit Ethernet
• Giga Bowser

External links

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• BIPM website

SI prefixes

Giga | Giga | Giga | Giga | Giga | Giga | 기가 | Giga | גיגה | Giga | ギガ | Giga | Giga | Giga | Giga | Giga | Гига | Giga | Giga | Giga