Giga byte

The gigabyte (/ˈɡɪɡəbaɪt/ GIG-ə-byt or /ˈdʒɪɡəbaɪt/) is a multiple of the unit byte for digital information. The prefix giga means 10⁹ in the International System of Units (SI). Therefore, one gigabyte is 1000000000bytes. The unit symbol for the gigabyte is GB.

This definition is used in all contexts of science, engineering, business, and many areas of computing, including hard drive, solid state drive, and tape capacities, as well as data transmission speeds. However, the term is also used in some fields of computer science and information technology to denote 1073741824 (1024³ or 2³⁰) bytes, particularly for sizes of RAM. The use of gigabyte may thus be ambiguous. Hard disk capacities as described and marketed by drive manufacturers using the standard metric definition of the gigabyte, but when a 500-GB drive's capacity is displayed by, for example, Microsoft Windows, it is reported as 465 GB, using a binary interpretation.

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