|Unit of Digital Information Storage|
|Gigabyte|| 109 Bytes|
|(larger units were proposed but have not yet formally been adopted by the BIPM)|
A gigabyte (GB), derived from giga- prefix, is an International System of Units (SI) unit of digital information storage equal to 1000 megabytes. This unit is part of IEC 80000-13 (International System of Quantities) which requires this unit to always equal 1000 megabytes. A closely related unit, gibibyte, is used to represent 1024 mebibytes.