Buy a Digital Camera

Capacity

Capacity isn't a major concern since all cameras allow you to insert additional memory cards into the camera to store your pictures on. Even still, you should consider the additional cost of memory that you'll most likely need. Some cameras do come with built in memory or one starter memory card, but the capacity is usually small and won't hold many pictures at high quality settings. With the low cost of memory cards these days it is probably more desirable for you to purchase a memory card and not have to worry about running out of room. Make sure you determine the type of memory card that your camera will need. The most common types are CompactFlash, Secure Digital (SD), Memory Stick, and xD. The most popular brand names are SanDisk, Lexar, Olympus, Sony (Memory Stick).

Batteries

Two points to consider here: (1) Does the camera use a proprietary battery that only works with that camera or does it run on standard batteries like AA's. (2) The battery life of the camera. Try to find out what the average running time of the camera under normal conditions until the batteries run out.

Proprietary batteries usually tend to perform better and they come with the charger included so you won't have to buy any batteries (but you may want to consider having a spare). It is also likely that a proprietary battery will increase the overall cost of the camera so you may find that many of the cameras at the low price range will run on standard AA batteries.

Many of the cameras you will be looking at will probably take AA batteries. If that is the case then you may want to look into purchasing NiMH rechargeable batteries since they have been show to perform quite well with digital cameras. The worst performers are regular alkaline batteries.

Battery life will also depend on how you use the camera. Turning it on and off more than usual or constant zooming will increase the load on the batteries causing them to drain quicker.

Look and Feel

It is important that you try to handle the camera before you buy. If you're thinking of purchasing it online then visit a local electronics store to try it out, assuming they have the model(s) you're looking to buy. The camera may have all the features you want but if you don't like the look and feel of it then you may be wasting your time.

Brand

In order to be confident that you're getting what you pay for it is advised that you stick with brand names when purchasing a digital camera. Canon, Panasonic, Kodak, Fuji, Minolta, Nikon, Olympus, Sony, etc.

Reviews

After narrowing it down most people will arrive at two or three cameras that they like feature wise and that are in their price range. Your best option now is to hit the internet and look for reviews on the cameras you're interested in to see which one performs better. By doing this you can easily find the weaknesses and strengths of the cameras you're interested in.

You can go to Google and search for 'make model review' where make and model are the make and model of the camera you're interested in. You can also visit sites such as Digital Photography Review and search for the camera you want to buy.

This is one of the most important steps that you should perform as it will give you a much clearer picture of the cameras capabilities (no pun intended).