version number

   A method of identifying a particular software or hardware release, assigned by the developer, that often includes numbers before and after a decimal point; the higher the number, the more recent the release.

   The number before the decimal point indicates the major revision levels (as in MicrosoftWindowsNT3andWindowsNT4), and the part after the decimal indicates a minor revision level (as in Windows NT 3.5 and Windows NT 3.51). In some cases, a minor revision can produce a significant difference in performance.

   Many people steer clear of any release labeled 1.0, because this number implies the first release of a product that may not have had extensive real-world use. Microsoft has avoided this issue with the release of Windows systems tied to the year, as in Windows 98 and Office 2000.