Description of Windows Defender definition updates
Content provided by Microsoft
Microsoft works to help make computing as secure as possible for our customers. As part of this effort, Microsoft Windows Defender regularly downloads updates to the definition files that are used to identify spyware and other potentially unwanted software. Windows Defender may also periodically download detection engine updates. Microsoft delivers these updates by using Microsoft Windows Update, Automatic Updates, and Windows Server Update Service (WSUS).
For more information about Windows Defender, visit the following Web site: