They have Image sensors, which are light sensitive chips placed in the camera where the film would normally be, they are used for image gathering. Most digital cameras can store a certain number of pictures, this is called image capacity, and varies from camera to camera. It also gives the options of storing 1,000 pictures with sound added to them, or 20min of motion pictures. Compression plays a big part in how images are stored and viewed on the computer. All commeras have, lenes with an f-number, and focal length.
Every camera has different features and therfore there is a wide variety in prices.
When looking for a digital camera you must match a price to the features that are desired. World wide shipments of digital cameras range between 3.8 million and 5.3 million units in 1998. The already significant price reductions of 30 percent per year will accelerate the growth of popularity amoung these cameras. This growth will mostly come from businesses rather than consumers. Business use these cameras to manipulate images into computer databases, presentations and web pages.