bezel
A bezel is the border between the screen and frame of a computer monitor, smartphone or any other computing device. Though largely aesthetic, bezels can help protect brittle materials from damage, such as chipped edges on the glass of an LCD screen. Often, a surrounding bezel is made of a secondary material, such as metal, which is added to protect the glass.
Recently, a trend in mobile electronic devices is a design with little to no bezel. Instead, the device has an edge-to-edge screen with no visible border. Because smartphones have touch interfaces and are mobile in nature, bezels have been commonly added to protect the devices' glass from breaking or shattering. However, consumer preference has trended toward devices with the largest screen size possible with fewer and fewer physical features, such as the iPhone’s home button, on the front of devices. Speakers, microphones and buttons have been relocated or made virtual in many smartphone designs to maximize the screen size for a given device. To ensure durability, some manufacturers use strengthened materials such as Gorrilla Glass.
Following consumer preference trends, computing device manufacturers are pushing a sleek, futuristic, bezel-less design where the entire device front is a screen. By narrowing the borders around a screen, smartphone manufacturers are able to give more of the phone's front to its display, which allows them to offer a bigger screen in a smaller phone.