Telephony - The science of converting sound into electrical signals and then transmitting those signals via copper wire, fiber optics, radio waves, etc. It may also be used to describe voice/data integration on computer networks. https://en.wikipedia.org/wiki/Telephony

Number Portability - This references your ability to possibly retain your existing telephone number(s) and the same quality of service when switching to a new locality or local telephone service provider.

Telcos - Telephone service providers.

The Telecommunications Act of 1996 - Among the changes is a wholesale revision of the FCC's rules and policies on local telephone companies' participation in video programming and delivery. The 1996 Act scrapped the FCC's old video dialtone (VDT) rules, which limited telcos to common-carriage video service and generally excluded them from programming. Telcos were then entitled to provide video programming and to do it through radio, common carriage, or a delivery medium called an Open Video System (OVS).

Overbuilder

See the Interactive Television Institute.