Sai Ram. First be clear about the intended use. Is it mainly for travel, and outdoor use? To photograph people, friends etc. or animals, far off scenery etc.? If people are the focus, face recognition and smile detection, red eye reduction etc. become important features. If far off scenes are important, optical zoom (not digital zoom) is important.

If night scenes are the main focus, good ISO ratings (less noise at high ISO settings), powerful built in flash plus a hot shoe for adding more flash units would be needed.

MP is good but above 8 or 10 MP, there is not much to choose. The sensor size and type make a difference.

Budget and brand preferences are the other factors to keep in mind. I will be glad to help you if you so desire.

Use user manual and get correct information

Best way would be to first decide on the purpose or possible uses of the camera.Then according to the intended use,the various factors like,lens type,shutter speed,zoom(more optical is better),resolution (anything above 5 megapixels is good for general use),preset photo modes(scenery,macro,sport,etc. modes),battery life(important if maximum outdoor use),lcd screen features,etc. can be decided.
Please state the exact purpose of digital camera.

Depending on budget and quality
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