A digital camera or digicam is a camera that captures photographs in digital memory. Most cameras produced today are digital and while there are still dedicated digital cameras, many more cameras are now being incorporated into mobile devices, portable touchscreen computers.However, high-end, high-definition dedicated cameras are still commonly used by professionals. Digital and movie cameras share an optical system, typically using a lens with a variable diaphragm to focus light onto an image pickup device. The diaphragm and shutter admit the correct amount of light to the image, just as with film but the image pickup device is electronic rather than chemical. However, unlike film cameras, digital cameras can display images on a screen immediately after being recorded, and store and delete images from memory.