A software routine that performs a particular task. It often refers to a routine that "handles" an exception of some kind, such as an error, but it can refer to mainstream processes as well. The term is typically used in operating systems and other system software. For example, the routine that opens, reads, writes and closes a database in a full-blown database management system (DBMS) is commonly separated into a stand-alone runtime module that is inserted into an application. In such cases, a "database handler" is said to be embedded within the app. See
DBMS.