WordPress hooks is the subject of interest to developers rather than none technical users however it is beneficial to understand the concept because majority of customization is based on hooks.
Hooks are programmatic actions and filters that can be used by developers to “hook into” some core WordPress functionality. For example AAM hooks into the functionality that retrieves the list of posts from the database and filter out all posts that are hidden for currently authenticated user or visitor.
The AAM User Activity extension uses hooks concept to listen to different events triggered by user actions and stores all related information and shows you the detailed report when requested.
There are few core WordPress functions that developers can use to register new hooks. Internally they are executed the same way with the only difference in return result. The add_action function does not return any result while add_filter action has to return the input value either unmodified or modified, otherwise it will break the chain of functions that may hook to the same event. It is also important to pay attention to the priority attribute as lower priorities are executed first.
A lot of access management tasks cannot be accomplished just with roles and capabilities that is why you may noticed that developers refer to different hook that can be utilized to accomplish desired objectives. Please do not hesitate to contact as with questions if you not sure how to accomplish some of the tasks and we are more than happy to help you out.