If you are using a semi-professional or professional grade camera you have probably at least heard the RAW format mentioned, but chances are you don't really know what that means, or why you should care.
One thing to clear up first is there are several RAW formats, each supported by a different camera manufacturer. The reason that all of these formats are grouped together and called RAW formats is because they essentially try to accomplish the same thing.
The real question is why should you use the RAW format provided by your camera? There isn't necessarily one answer to that question, and there are some cases in which it would be a good idea to not use raw, but in general it is recommended.
The single biggest reason to use a RAW format is because you then have a file with the data essentially exactly the way the sensor captured it. This is an advantage in two ways. First, you have a much cleaner file than the JPEG files, because JPEG compresses information in a way which adds noise along color and contrast edges. Second, you are able to do much of the same processing that the camera does internally, after the fact, allowing for greater customisation of the final look of the picture.
Look for next weeks tip for info on UFRaw, a RAW processing software.