The time of day when phone lines are most in demand.

Zero plus dialing. An operator assisted long distance call which is charged to the calling party. "00+" or "00-" (OCC) (AOS)

1 -

The ability to send calls over a carrier other than a caller's primary carrier by dialing "101-XXXX" then "1+" the long distance number, where "XXXX&a [..]

8 -

Service which allows callers to listen to recorded messages such as horoscopes, 'adult' dialogue, stock market or sports reports by calling 976-xxxx. The local telephone company charges call [..]

Preprogramming of a caller's phone system or long distance company's switch to recognize a 2- to 4-digit number as an abbreviation for a frequently dialed phone number, and automatically dia [..]

A telephone circuit which connects a customer location to a network switching center.

Calculated point-to-point mileage between terminal facilities. ALL TRUNKS BUSY (ATB)

A secondary communications path used to reach a destination if the primary path is unavailable. ALTERNATE USE (AU)