We have seen that CICS act as an interface between operating system and application program and this is achieved by management module. In other words Management Modules are programs that act as interface between operating system and application program. Control table is associated with management module and is used to define the CICS environment.
A control block is used to store information about CICS system. For instance we have seen that a transaction handled by CICS is identified by transaction identifier. And also each transaction may have number of task in it. Control blocks have the information about the task in an area called as task control area. Like that control block has many system information stored.