Telephony
![A commercial IP telephone, with keypad, control keys, and screen functions to perform configuration and user features.](/Images/godic/202501/09/Cisco7960G4737.jpg")
![Fixed telephone lines per 100 inhabitants 1997–2007](/Images/godic/202501/09/Fixed_telephone_lines_per_100_inhabitants_1997-2007_ITU4737.png")
Telephony (/təˈlɛfəni/ tə-LEF-ə-nee) is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is intimately linked to the invention and development of the telephone.