A queue table is jargon. It is used to describe a technique or method for storing a list of jobs or items to be addressed. The idea is that these things have been placed in a queue and will be handled at a later time.
The basic idea is to create a table that stores the information needed to attend to the item at hand.
This makes for more efficient processing scripts or calculations as those only need the id of the item to retrieve all its info instead of passing all the information using a variable, JSON or other method.