1. An automatic system of switching electric circuits using semiconductor devices; such as, transistor combinational circuits, semiconductor diode matrices, and integrated circuits, to perform the selection and switching in telephone circuitry.
2. A telephone switching system which uses a computer with a storage-containing program switching logic, whose output actuates switches that set up telephone connections which perform most telephone central office switching functions automatically.

Electronic switching systems permit custom-calling services; such as, speed dialing, call transfer, and three-way calling.

3. The use of electronic circuits to perform the functions of a high-speed switch.