With computers, eight binary bits together is called a "byte". The size of files is commonly measured in "kilobytes" or "megabytes" (sometimes in "gigabytes"). A kilobyte is 1000 bytes. A megabyte is 1000 kilobytes, a gigabyte is 1000 megabytes and a terabyte is 1000 gigabytes. Sometimes, it is easier to measure bytes in groups of 1024, since 1024 is a power of 2. There are 1024 bytes in a "kibibyte", 1024 kibibytes in a "mebibyte", and 1024 mebibytes in a "gibibyte". 