A gigabyte is a measurement of computer data storage capacity.This measurement is roughly equivalent to 1 billion bytes.
Often written simply as GB, this is the term typically used to describe disc space, or data storage space, system memory, and it can also be used to describe the speed of data transfer with gigabytes per second, Gbps.
The definition of a megabyte can vary, with IBM saying that it is 1,000,000 bytes in decimal notation for when referring to describe disc storage capacity. When it is used for real and virtual storage, and channel volume, 2 to the 20th power or 1,048,576 bytes is the appropriate notation.
So 1,024 megabytes equals a gigabyte and 1,024 gigabytes equal a petabyte when it comes to processor or virtual storage. However, when it comes to disc storage, 1,000 megabytes equals a gigabyte and 1,000 gigabytes equals a petabyte.
One Bit is the smallest unit of data that a computer users and a Byte is equal to 8 Bits. A Byte can represent 256 states of information, for example, numbers or a combination of numbers and letters.