Digital cameras produce digital pictures that are easy to load onto a computer and email around the world. Digital pictures are also easy to check and delete. So if it is obvious that a picture is hopeless it can be easily deleted rather than wasting film, which cannot be reused. Without the film, which can go bad with age, a digital camera that you keep handy in case of need is far more reasonable.

One way to characterize digital cameras is by image size. The pictures are made up of tiny dots of color, called pixels. This is expressed as a pair of numbers, height and width. An example would be 320x480. These numbers would then be multiplied together, and larger numbers are more detailed, but typically are on more expensive cameras.

At this point, two megapixels, essentially two million pixels, is on the low end and might result in noticeable defects when pictures are enlarged. Five megapixels is a robust picture that can usually handle enlargement well.

Another consideration is zooming. Optical zoom adjusts the actual light as it enters the camera to make the scene appear closer. Digital zoom adjusts the picture after it has been digitized to simulate a closer appearance. While both can produce acceptable results, optical zoom is preferred.

Digital cameras come with some internal storage. This is almost always too small. Thus the type of add-on storage the camera allows is important. In some cases you might possess other equipment that uses the same sort of gear, and compatibility is helpful. While there are several choices, this additional storage is typically a chip about the size of a thumbnail, allowing several to be conveniently carried if needed.

It is important to pay attention to the battery. Some cameras will use standard sizes, others will use proprietary or less common sizes. Some are better able to hold a charge, some cameras are power hogs, and some systems are rechargeable.

This brings us to the preview screen. This is an LCD screen that shows what the camera would see at any point, should you desire a picture. In this mode, the screen is active whenever you are considering a picture, which tends to consume batteries at an alarming rate.

Even digital cameras also come with an optical viewfinder that consumes no power. There are circumstances that make this superior, such as waiting for the correct moment to shoot, and circumstances that require the preview screen, such as composing a picture at a very awkward angle. The screen also allows you to preview the saved pictures and delete any that are unusable to clear storage space.