Terabyte

A terabyte is a unit of measurement in computers of approximately one million million (American trillion) bytes.

Because of irregularities in definition and usage of the kilobyte, the exact number could be any one of the following:

1. 1,099,511,627,776 bytes - 1024 times 1024 times 1024 times 1024, or 2⁴⁰. This is 1024 times a gigabyte. This is the definition used in computer science and computer programming

1. 1000000000000 bytes - or 10 ¹².

See integral data type.

A petabyte is 1024 times an terabyte.

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To clarify the meaning(1) above, the International Electrotechnical Commission (IEC), a standards body, in 1997 proposed short unions of the International System of Units (SI) prefixes with the word "binary." Thus meaning (1) would be called a tebibyte. (Gi) This naming convention has not been widely accepted.

links:

http://www.quinion.com/words/turnsofphrase/tp-kib1.htm

http://www.nist.gov/public_affairs/techbeat/tb9903.htm