Around 1960, the Bell System developed an automated console switch- board to handle operator-assisted long distance calls. These included collect, person-to-person, credit card, third-number billing, and time-and-charges.
For the caller, the big change was to dial 0 + area code + number. For the telephone company, this allowed the switching equipment to connect the call and record billing information instead of the operator connecting it manually hand via cords and recording the information by hand on a toll ticket. It was a huge boost in productivity. In addition, on pay phone calls, the console screen told the operator how much money was needed, eliminating a rate table look up.
The system was known as TSP, Traffic Service Position. An improved version was known as TSPS, or Traffic Service Position System.
Today, all of that is essentially obsolete. Long distance telephone calls today are so cheap there is little need for those special classes of calls. Payphones are almost gone.
Advertisement in LIFE magazine in 1961.
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