• The Windows 10 operating system is a major update to Microsoft's Windows NT operating system. It's the immediate successor to Windows 8.1, which came out over two years ago. On July 15, 2015, it was released to manufacture, and on July 29, 2015, it was distributed to retail.
• Beginning with Windows 10, version 21H2, feature updates for Windows 10 are published to the General Availability Channel once a year, in the second half of the calendar year. Depending on the lifespan policy, they will receive monthly quality updates for 18 or 30 months from the date of release.

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