Currently the usual is 1 Gigabyte (GB) = 1000 Megabytes (MB). But it wasn't always like that.
For the long term, 1 Kilobyte=1024 bytes, 1 Megabyte = 1024 kilobytes, 1 Gigabyte = 1024 megabytes, and so on. The motive is the reality that it is less complicated to do binary math whilst running with powers of.
However, the prefix "kilo" way a thousand, and now not 1024, and the same reasoning applies for "mega", "giga", and many others. So some human beings used 1 Kilobyte as being a thousand bytes. It all has become very puzzling.
The International Electrotechnical Commission proposed in 1998 the nomenclature of 1 Kibibyte (KiB) = 1024 bytes, 1 Mebibyte (MiB) = 1024 KiB, 1 Gibibyte = 1024 MiB, ... You get the concept.
So, nowadays all primary standards take into account that 1 Kibibyte (KiB) = 1024 bytes, and 1 Kilobyte (KB) = a thousand bytes. This is what garage producers currently use.
However, a variety of antique software nonetheless makes use of the old nomenclature. And a few new software program written using folks that do not know or don't care approximately this distinction.