A megabyte is 2 to the 20th power (approximately 1 million) and a gigabyte is 2 to the 30th power (approximately 1 billion).

In computer literature, kilobyte is usually abbreviated as K or KB. To distinguish between a decimal K (1,000) and a binary K (1,024), the IEEE has suggested following the convention of using a small k for a decimal kilo and a capital K for a binary kilo, but this convention is by no means strictly followed.