Runmodes
Runmodes are not groups, but they can provide a similar function at some levels. Runmodes let you 'tag' a resource with a runtoken, and then define runmodes as sets of runtokens. The INGRUN command can be used to activate or deactivate particular runmodes. Resources whose runtokens are not selected get shutdown.
It is strongly suggested that runmodes rather than large groups containing unrelated resources be used for 'bulk' application control on a system.
To learn more about runmode and try this feature in a simulated System Automation environment, check this hands-on tutorial.