For example , the plain old telephone service ( POTS ) is a telephony application feature at one level , but itself is composed of originating features and terminating features .
Similar to many concepts in computer science , the term can be used at different levels of abstraction .
The plain old telephone service ( POTS ) is a telephony application feature at one level , but itself is composed of originating features and terminating features .
Similar to many concepts in computer science , the term can be used at different levels of abstraction .