In a digital camera the shutter release is pressed and an image is projected by the camera lens onto a chip that is less than 0.25 in. Each pixel is a picture element with its own electrical charge. Camera circuits convert each pixel's charge into a digitized information number. The sharper pictures are obtained by using more and more pixels. The basic digital camera has a chip of 640 pixels horizontal and 480 pixel vertical giving a total pixel count of over 300,000.
Digital cameras are similar to computers in that the amount of memory is very important.
Additional memory cards can be purchased and installed doubling or even quadrupling the storage capacity. The digital camera is all electronic. A large rechargeable battery can handle 300 pictures per charge. Some digital cameras are equipped with small LCD screens and this circuitry requires additional battery power.