Netro Support: Microsoft Windows

Overview
For security, please use the latest version of Windows and ensure all the latest software updates are installed.
To protect your data, backup regularly.

Links
Microsoft Windows
Which Windows operating system am I running? Using "About your PC" or winver, including OS Build.
Lifecycle FAQ - Windows
Windows 10 release information Showing "Microsoft recommends" version.
Download Windows 10 Update Assistant and Media Creation Tool, e.g. .iso USB image.

Update Windows 10
Windows Update: FAQ
Windows 10 update history Showing latest OS Builds & release history.
Windows Support
Windows Blog

Wikipedia: Microsoft Windows
Wikipedia: Windows 10 version history
Wikipedia: Windows Update

Links
Backup

Updated Jan-21, please report broken links to support.