Slider (mobile phones)

The form factor of a mobile phone is its size, shape, and style, as well as the layout and position of its major components. There are three major form factors – bar phones, flip phones, and sliders – as well as sub-categories of these forms and some atypical forms.

A bar (also known as a slab, block, candybar) phone takes the shape of a cuboid, usually with rounded corners and/or edges. The name is derived from the rough resemblance to a chocolate bar in size and shape. This form factor is widely used by a variety of manufacturers, such as Nokia and Sony Ericsson. Bar-type smartphones commonly have the screen and keypad on a single face. The Sony Ericsson has a well-known 'MarsBar' phone model CM-H333.

"Brick" is a slang term almost always used to refer to large, outdated rectangular phones, typically early devices with large batteries and electronics. Such early phones, such as the Motorola DynaTAC, have been displaced by newer smaller models which offer greater portability thanks to smaller antennas and slimmer battery packs.

However, "brick" has more recently been applied to older phone models in general, including non-bar form factors (flip, slider, swivel, etc.), and even early touchscreen phones as well, due to their size and relative lack of functionality compared to current models on the market.

The term "brick" has also expanded beyond smartphones to include most non-working consumer electronics, including a game console, router, or other device, that, due to a serious misconfiguration, corrupted firmware, or a hardware problem, can no longer function, hence, is as technologically useful as a brick. The term derives from the vaguely cuboid shape of many electronic devices (and their detachable power supplies) and the suggestion that the device can function only as a lifeless, square object, paperweight or doorstop. This term is commonly used as a verb. For example, "I bricked my MP3 player when I tried to modify its firmware." It can also be used as a noun, for example, "If it's corrupted and you apply using fastboot, your device is a brick." In the common usage of the term, "bricking" suggests that the damage is so serious as to have rendered the device permanently unusable.

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Wikipedia