[1] : The Collaborative International Dictionary of English v.0.48

call-back \call-back\ n.
   1. a return call, especially a telephone call.
      wordnet 1.5

   2. the recall of an employee to work after a layoff.
      wordnet 1.5

[2] : WordNet (r) 2.0

call-back
     n 1: a return call
     2: the recall of an employee after a layoff

[3] : WordNet (r) 2.0

callback
     n : a request by the manufacturer of a defective product to
         return the product as for replacement or repair syn: recall
see also:
recall 

[4] : The Free On-line Dictionary of Computing (27 SEP 03)

callback
     
        1.  a scheme used in event-driven programs
        where the program registers a subroutine a "callback
        handler" to handle a certain event.  the program does not
        call the handler directly but when the event occurs, the
        run-time system calls the handler, usually passing it
        arguments to describe the event.
     
        2.  a user authentication scheme
        used by some computers running dial-up services.  the user
        dials in to the computer and gives his user name and
        password.  the computer then hangs up the connection and
        uses an auto-dial modem to call back to the user's
        registered telephone number.  thus, if an unauthorised person
        discovers a user's password, the callback will go, not to him,
        but to the owner of that login who will then know that his
        account is under attack.
     
        however, some pabxs can be fooled into thinking that the
        caller has hung up by sending them a dial tone.  when the
        computer tries to call out on the same line it is not actually
        dialing through to the authorised user but is still connected
        to the original caller.
     
        3.  cost control callback.
     
        2003-07-13
     
     
see also:
event-driven subroutine event run-time system user authentication dial-up 
user name password auto-dial modem pabx 
cost control callback 

Callback >> C Words
Callback, definition of term: Callback
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