Barred: Stops patrons from using their library cards; alerts the staff that the patron is banned/barred from the library. The “check-out” functionality is disabled for barred patrons (NO option to override – the checkout window is unusable and the bar must be removed from the account before the patron is able to checkout items).  These patrons may still log in to the OPAC to view their accounts.

Blocked: Often, these are system-generated blocks on patron accounts. 

Some examples:

A notice appears when a staff person tries to checkout an item to blocked patrons, but staff may be given permissions to override blocks.