clamshell

A clamshell design is a kind of form factor for electronic devices in the shape of a clamshell. Mobile phones, handheld game consoles, and especially laptops, are often designed like clamshells. Clamshell devices are usually made of two sections connected by a hinge, each section containing either a flat panel display or an alphanumeric keyboard/keypad, which can fold into contact together like a bivalve shell.
A clamshell mobile phone is sometimes also called a flip phone, especially if the hinge is on the short edge. If the hinge is on a long edge (e.g., Nokia Communicators), the device is more likely to be called just a "clamshell" rather than a flip phone.Generally speaking, the interface components such as keys and display are kept inside the closed clamshell, protecting them from damage and unintentional use while also making the device shorter or narrower so it is easier to carry around. In many cases, opening the clamshell offers more surface area than when the device is closed, allowing interface components to be larger and easier to use than on devices which do not flip open. A disadvantage of the clamshell design is the connecting hinge, which is prone to fatigue or failure.

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