it also depends on who you are
e.g. technically
a bit is a 1 or zero
a byte is 8 bits(over 8 is called a 'word', 4 bits is called a 'nibble') Data transmission is measured in KiloBits/sec(kbps, note small k)
a kilobyte(Kb) is 1024 bytes (2^10)(note big K)
a Megabyte(Mb) is 1024 Kb (again 2^10)
a Gigabyte(Gb) is 1024 Mb
etc
However when you buy Hard drives for example they class a Gb as 1000 Mb
so a 80 Gb Hard disk is actually only 78 1/4 Gb, then you format it and lose a bit more
