Microsoft continuously collects feedback on Windows 7 and Windows Server 2008 R2 operating systems from its customers and partners. This feedback results in enhancements that help improve compatibility, reliability, performance, and user experience.
These enhancements are typically made available in the form of regular updates delivered via Windows Update and, in some cases, the Microsoft Download Center. All updates are then rolled-up, along with additional enhancements, into a single package called a Service Pack. By integrating these updates into a thoroughly tested single service pack, Microsoft aims to provide a single high-quality update that will minimize both deployment and testing complexity for customers.