The touch tone telephone is a communication device that makes use of a form of telephone switching that is known as dual-tone multi-frequency. DTMF replaced the earlier pulse style of switching that was common with the rotary dial phones commonly used through the 1970’s. A simple telephone keypad replaced the rotary dial on the newer touchtone telephone units that are now the industry standard for both cell phones and landline service.

Development of touchtone services began in the middle of the 20th century, and were first introduced to a wide sector of the consumer market in the early 1970’s. The basic process of the new tone dialing made it possible to switch calls with more efficiency, and also created the means of using specific tones to access a range of ancillary services that were not possible with the traditional pulse signal.

In order to take full advantage of these new capabilities, major telephone service providers around the world began to order the manufacture of touch tone phones that would accurately emit the right type of tones to activate those features. Deployed to the business community initially, the phenomenon quickly spread to the private sector. By 1979, the touch tone phone was definitely the telephone of choice.

With the deregulation of the telephone industry in the United States in 1984, the touch tone telephone became even more important. Companies that specialized in particular telephone communication services began to compete with the main telephone carriers for business. Making use of the dual tone technology associated with the touch tone telephone helped many independent conference call companies capture a profitable share of the market for those types of service.

The presence of touchtone telephones in the home also made it possible for businesses to provide enhanced customer service as well. The touch tone telephone made it possible for banks to set up direct access to information about current balances, latest activity, and pending deposits by making use of the dual tone functionality. As time went on, other companies found ways to implement automated technology that allowed callers to reach the right contact or obtain account information by simply pressing keys on the touchtone phone keypad.

Today, the touch tone telephone is the most common type of phone in use in the United States and many other countries around the world. Both landline services, newer Voice over IP applications, and current cell phone technology all have their basis in the functionality of the touch tone telephone.