Bit Byte Megabyte Gigabyte

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Measurements for
Memory & Storage
The following table shows the prefixes/multipliers of BYTES
Increases are in units of approximately 1000
(actually 1024). See: EXPLANATION1 bit (binary digit*) = the value of 0 or 18 bits = 1 byte1024 bytes = 1 kilobyte1024 kilobytes = 1 megabyte1024 megabytes = 1 gigabyte1024 gigabytes = 1 terabyte1024 terabytes = 1 petabyteAbbreviations1 kilobyte = 1 k1 megabyte = 1 MB1 gigabyte = 1 GB1 terabyte = 1 TB1 petabyte = 1 PBSize in "bytes"Kilobyte (KB) = 1,024Megabyte (MB) = 1,048,576Gigabyte (GB) = 1,073,741,824Terabyte (TB) = 1,099,511,627,776Petabyte (PB) = 1,125,899,906,842,624EXPLANATIONS and NOTES
The Decimal System is a base 10 number system that uses ten digits (0,1,2,3,4,5,6,7,8,9).
1000 is attained as follows:
1 x10 = 10 x 10 = 100 x 10 = 1000 (kilo)

The Binary System is a base 2 number system that uses only two (bi) numbers or digits (0 and 1) to represent all values.
The unit closest to 1000 is attained as follows:
1 byte x 2 = 2
x 2 = 4
x 2 = 8
x 2 = 16
x 2 = 32
x 2 = 64
x 2 = 128
x 2 = 256
x 2 = 512
x 2 = 1,024 bytes (1 kilobyte) 

A "2 gig hard drive" means the drive holds "2 gigabytes" (2,147,483,648 bytes). Just one CD can hold 650 MB, so 2 GB could be filled with about 3 CD's.
Terabyte databases are becoming common, and rumor has it that there are probably a few