The gibibyte, It is the information unit multiple of the byte used by the binary base.

1 GiB equals 1024 mebibyte (MiB) = 1,073,741,824 bytes.
Not to be confused with Gigabyte (GB), it uses the decimal base.
The capacity of a storage unit is usually expressed in GB, not the operating systems or the RAM used by the GiB. 1 GB = 10(9) bytes = 1,000,000,000 bytes ≈ 0.93 GiB 1 GiB = 2(30) bytes = 1,073,741,824 bytes ≈ 1.07 GB
To clarify a bit more; In decimal base (also called International System): kilobyte (KB), megabyte (MB), gigabyte (GB), terabyte (TB), petabyte (PB), exabyte (EB), zettabyte (ZB), yottabyte (YB) binary base: kibibyte (KiB), mebibyte (MiB), gibibyte (GiB), tebibyte (TiB), pebibyte (PiB), exbibyte (EiB), zebibyte (ZiB), yobibyte (YiB)

The Operating Systems use;
Mac OS: Decimal.
GNU/Linux: decimal.
Windows: binary for quantity, but with decimal nomenclatures.