Queues support the dynamic nature of transaction processing and offer flexibility in application construction. Queues provide scratchpad support, asynchronous communications between applications, transaction batching, general data storage and many other capabilities.

Queues are used to pass the huge amount of data between the application programs or transactions. Queues normally transfers the data which is more than 32K length.

Queues can pass the data between the transactions in the same region or in the other region. Queues are divided into two types based on its behaviour and usage -

Queue Description
Temporary Storage Queue (TSQ) CICS facility that makes the storing data available to multiple transactions.
Transient Data Queue (TDQ) Used to store the data for subsequent internal or external processing.