How many megapixels should my camera have?

The more megapixels (MP) you have, the higher the resolution of your photos. Higher resolution is important for enlarging photos, or cropping and enlarging portions of them. This chart shows how large a photo you can print in relation to your camera's megapixels.

A 6 to 8 MP camera will equal that for most purposes. On a pocket style camera, ignore all digital zoom claims. look for a good optical zoom. 3X is okay, higher is better for long shots. In pocket cameras look for one that uses AA batteries rather than proprietary ones that require cables and charges.

In an article by by Marty Rubenski Digital Cameras: How Many Pixels Do I Need?

He says :

Higher megapixel cameras do have some drawbacks. The first, and most obvious, is price. A basic 5.0 megapixel camera currently runs between $200 and $300. A 1.2 megapixel camera can be had for less than $50.

Storage for those large pictures will also cost you more. A 32 MByte memory card will hold around a hundred 1.2 megapixel pictures. This drops right down to around 60 pictures for 2.0 megapixels and to around 40 pictures for a 3.0 megapixel model. One other consideration, not often mentioned, is that a higher megapixel camera has to do more work to compress and store images, leading to longer waits between picture shots and viewing.

Before you rush off and spend $300 for a camera, consider what you will be doing with the pictures. Are you viewing them just on your computer? Sending them as email attachments? Printing them on an existing inkjet printer? Having them professionally printed?