GB

From AudioLexic

A gigabyte (derived from the SI prefix giga-) is a unit of information or computer storage equal to one billion (short scale, meaning a thousand million) bytes. It is commonly abbreviated GB (not to be confused with Gb, which is used for gigabits).

Because of a traditional inconsistency, "gigabytes" are often intended to mean gibibytes in common speech. This usage is not recommended as it creates confusion (see below).

[edit] Definition

There are two slightly different definitions of the size of a gigabyte in use:

• 1,000,000,000 bytes or 10⁹ bytes is the decimal definition used in telecommunications (such as network speeds) and most computer storage manufacturers (such as hard disks and flash drives). This usage is compatible with SI. Quotes from Seagate: "The storage industry standard is to display capacity in decimal", and, "One gigabyte, or GB, equals one billion bytes when referring to hard drive capacity". Similar quotes are found on the websites of other storage manufacturers.
• 1,073,741,824 bytes, equal to 1024³, or 2³⁰ bytes. This is the definition commonly used for computer memory and file sizes. The International Electrotechnical Commission recommends that this unit should instead be called a gibibyte (abbreviated GiB), as it conflicts with SI units used for bus speeds and the like. Microsoft, for instance, uses this definition to display hard drive and file sizes.

[edit] Gigabytes vs gigabits

In conventional modern usage, a byte is 8 bits. One gigabyte is equivalent to eight gigabits.