Joomla Cache Settings. 

Joomla has built-in cache management system

1) Caching System

To enable caching, go to Global Configuration > System > Cache setting, and switch Cache to “ON – Conservative caching” or “ON - Progressive caching".

where    --> “Conservative caching” will use the caching setting of each module,     

and       --->“Progressive caching” will override the caching setting whether you set it or not.

2) Page caching

To enable, in the control panel, go to Extensions/ Plugins/ Find “System - Page cache” and switch the Use Browser setting to “Yes”