Petabyte
A petabyte is a unit of measurement in computers of one thousand million million (short-scale quadrillion) bytes. Its abbreviation is PB.
Because of irregularities in definition and usage of the kilobyte, the exact number in common practice could be either one of the following:
- 1,000,000,000,000,000 bytes - or 10 15.
- 1,125,899,906,842,624 bytes - 10245, or 250. This is 1024 times larger than a terabyte. This is the definition most often used in information storage.
An exabyte is 1024 times larger than a petabyte.
The San Diego Supercomputer Center (SDSC) in the USA has a 1 petabyte hard disk store and a 6 petabyte robotic tape store, both attached to the National Science Foundation's TeraGrid network. [Source: Electronics Weekly, Dec 11, 2002]
The Internet Archive Wayback Machine contains approximately 1 petabyte of data and is currently growing at a rate of 20 terabytes per month. [Source: ]
To clarify the distinction between decimal and binary prefixes, the International Electrotechnical Commission (IEC), a standards body, in 1998 defined new prefixes by combining the International System of Units (SI) prefixes with the word "binary" (see Binary prefix). Thus meaning (2) is called by the IEC a pebibyte (Pib), and meaning (1) is called by the IEC a petabyte. This naming convention has not, as of 2004, been widely adopted.
The prefix "peta" is an alteration of "penta", the Greek word for 5.
See also
