3 of 17Image
Windows has included an update utility since Windows 95, and Automatic Updates were introduced with Windows Me in 2000.
It wasn’t until 2003, however, that Microsoft systematized its process for issuing security updates. Security updates are provided on the second Tuesday of each month—Patch Tuesday. Non-security updates are provided on the fourth Tuesday of each month. Microsoft began this program so that corporate customers could plan for testing and installation of security updates. Although it was a controversial decision, today it’s generally regarded as effective.
On rare occasions—once a year or so—Microsoft releases an “out of band” update to address an issue that can’t wait till the next month’s Patch Tuesday.