What is the difference between a rotary dial and a touch-tone phone?

A rotary dial phone is a type of telephone that uses a rotating dial to dial a phone number. The dial has numbers and letters printed on it, and the user rotates the dial to select the desired number or letter. As the dial rotates, it interrupts the electrical current in the phone line, sending a series of pulses to the telephone exchange that correspond to the selected number or letter.

A touch-tone phone, on the other hand, uses a keypad with buttons that produce different tones when pressed. Each button corresponds to a specific frequency of sound, and the phone uses these frequencies to signal the telephone exchange which number or letter has been selected. Touch-tone phones are faster and more efficient than rotary dial phones, and they allow for additional features like automated phone menus and voicemail.