Job-control language refers to the set of commands that are used to control and manage batch processing in computer systems. Some synonyms for this term include job language, JCL, and batch job language. JCL commands are essential in controlling the sequence of execution of programs in a batch job. Other synonyms for job-control include job scheduling language (JSL), Job Entry System (JES), and Input/Output Control System (IOCS). These commands are mostly used in mainframe computer systems, which run batch processing. Job-control language is an essential aspect of computer systems that enables users to effectively manage batch jobs and ensure they are executed in the right sequence.