Service Pack
The leftmost digit, .x000, is the service pack release number (for example, 2.00.1239.2000 denotes Service Pack 2). By default service pack 2 will contain all of service pack 1. Microsoft documents all components of each service pack on their website http://support.microsoft.com
This convention has changed slightly with Windows Vista SP1. With Windows Vista the build string is shown as 6.0.6001.18063 with the last digit (x) of the 600x number representing the service pack (ex: 6001 = SP1, 6002 = SP2) and everything after as the exact build number.
Read more about this topic: Microsoft Version Numbering
Famous quotes containing the words service and/or pack:
“Our chief want in life, is, someone who shall make us do what we can. This is the service of a friend. With him we are easily great.”
—Ralph Waldo Emerson (1803–1882)
“The savage soul of game is up at once—
The pack full-opening various, the shrill horn
Resounded from the hills, the neighing steed
Wild for the chase, and the loud hunter’s shout—
O’er a weak, harmless, flying creature, all
Mixed in mad tumult and discordant joy.”
—James Thomson (1700–1748)