In photography, the shutter-release button (sometimes just shutter release or shutter button) is a push-button found on many cameras, used to record photographs.[1] When pressed, the shutter of the camera is "released", so that it opens to capture a picture, and then closes, allowing an exposure time as determined by the shutter speed setting (which may be automatic). Some cameras also utilize an electronic shutter, as opposed to a mechanical shutter.
The shutter-release button is one of the most basic features of a dedicated handheld camera. Mobile devices such as modern smartphones have a touchscreen button for capturing photos, but also have a physical shutter button as well, as the sound volume buttons are used as such, with exception of some phones having a dedicated shutter button.
The term "release" comes from old mechanical shutters that were "cocked" or "tensioned" by one lever, and then "released" by another.[2] In modern or digital photography, this notion is less meaningful, so the term "shutter button" or simply "capture button" is more used.