A cache is a mechanism for temporarily storing (caching) data in memory in order to reduce access time to data stored on disk drives.
Caching can be more generalized to refer to temporarily storing (caching) data locally in order to reduce access time to data stored far away. It can include CPU caching but for this Database Administrators site, it is primarily associated to disk caching. For databases, caching can occur on many levels, including SQL execution plans, metadata, stored procedures, and actual database data. Include tags for database vendor and release, and any appropriate related tags such as: