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## Input Devices ### Digital Cameras Unlike the old-style film cameras, which used photographic film to store a picture, digital cameras capture an image and store it in memory as long strings of numbers. A digital camera does not use ilm. When you press the button to take a photograph with a digi...

## Input Devices ### Digital Cameras Unlike the old-style film cameras, which used photographic film to store a picture, digital cameras capture an image and store it in memory as long strings of numbers. A digital camera does not use ilm. When you press the button to take a photograph with a digital camera, an aperture (opening) opens at the front of the camera and light streams in through the lens. The incoming light hits the image sensor chip, which breaks it up into millions of pixels. The larger the number of pixels that a camera has, the clearer the image and the more detail it can capture. The sensor measures the color and brightness of each pixel and stores it as a number. Your digital photograph is stored as a long string of numbers describing the exact details of each pixel it contains. **Figure 2.21 A digital camera** A digital camera has the following advantages: - It gives us instant photographs. - It allows us to edit our pictures. - It makes it easier for us to print or share photographs using smartphones, email and websites. In addition, the memory in a digital camera can be erased so that more images can be captured. ### Smart Cards A smart card (also called a chip card) is one of the main ways people make most payments today. This card is similar to the debit card used in ATMs except for one major difference. The smart card has a small microchip attached to it, which makes it very secure and gives it an advantage over the magnetic strip cards. While the magnetic strip on the back of normal cards can be altered or forged, it is difficult to tamper with the computer chips attached to smart cards.