Windows Update

Windows Update is a Microsoft service that downloads and installs software updates, drivers, and security fixes for Windows devices.

Windows Update client: The Windows component that scans for, downloads, and installs updates from update sources. It coordinates the device-side work of checking for and applying updates.
Microsoft Update Catalog: A Microsoft website for finding and downloading individual Windows and Microsoft product updates. It provides manual access to update packages outside automatic delivery.
Microsoft Store: Microsoft's digital storefront for acquiring and updating apps and other digital content. Store app updates use a different delivery and management path from Windows system updates.
Patch Tuesday: Microsoft's regular monthly release date for security updates, usually the second Tuesday of each month. It anchors the predictable schedule for many Windows security releases.
Windows Update Agent: A Windows component that manages update detection, download, and installation. It provides the client machinery behind many Windows Update operations.
Windows Server Update Services: A Microsoft server role that distributes updates to managed computers on a network. Administrators can approve updates centrally before devices receive them.
Windows feature update: A Windows release that adds features and may change the operating system's version. It is a broad release category, unlike smaller monthly security updates.
Zero-day vulnerability: A software vulnerability exploited before an effective fix is available or widely deployed. Rapid update delivery can limit exposure after a vulnerability is patched.
Windows Update Medic Service: A Windows service that helps repair and protect Windows Update components. It can restore update components when they become damaged or disabled.
Microsoft Intune: A cloud service for managing devices, applications, and security policies. It can configure update policies for enrolled Windows devices.

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