service pack - Computer Definition
A collection of software fixes and enhancements that is applied to an installed version of an operating system. Always a major update, service packs are typically downloaded from the Web as part of an automatic update service. The modifications within the service pack are built into subsequent versions of the OS distributed on CD or DVD. Versions are identified as SP1, SP2, etc.; for example, "Windows XP SP2." See adaption kit upgrade and feature pack.