A pocket is where the jetty and the beach meet, either side of the jetty. A hole is a deeper area in an area that is usually flat or of one consistant depth. At the end of a jetty you will find a rip. This is where the current that is moving northward or southward hits the jetty.
This current movement usually causes or cuts a hole where bass or blues may sit and wait for forage to be swept around the jetty tip in the current. Hope this helps.