Official description : Windows 7 Service Pack 1 (SP1) is an important update that includes previously released security, performance, and stability updates for Windows 7. Installing SP1 helps keep Windows 7 up to date.

Windows 7 Service Pack 1 (SP1) is an important update that includes previously released security, performance, and stability updates for Windows 7. SP1 also includes new improvements to features and services in Windows 7, such as improved reliability when connecting to HDMI audio devices, printing using the XPS Viewer, and restoring previous folders in Windows Explorer after restarting.

Installing SP1 helps keep Windows 7 up to date. For information on how to get SP1, see Learn how to install Windows 7 Service Pack 1 (SP1).