Clamshell

In the United States, a phone that opens up to reveal the keypad, microphone, and earpiece; these are typically more compact than other designs. Often called "flip phones" (although 'flip phone' is a trademark of Motorola). Clamshell phones became very popular in the United States after the introduction of Motorola's StarTAC in 1996. While this style of referred to as a "clamshell" (a term that is already outdated), few if any people referred to their telephone as a clamshell. Rather, this term is used to refer to the cell phone style.