Almost all digital cameras (at-least the decent ones) support a format like RAW. RAW is the generic term given to unprocessed image files that most digital cameras create right off their sensor- like CRW in case of Canon and NEF for Nikon. In most instances, the file is converted to JPG or TIFF format to make it viewable in the camera or print direct to the printer, since JPG is almost universally understood. However, many people love to get their hands on this raw data dump to convert it on their PC and have more control on the finished product. The relatively smaller file size of RAW files compared to its non lossy equivalent - TIFF is another attraction.
 
All in all, RAW can be described as a negative, and the conversion algorithms as the developing/printing process that we had in the film world. The issue here is that every camera manufacturer has its own version of RAW, by some estimates there are almost 100 RAW format out there. The only way you can read a RAW file is by using the camera makers' software or hoping that a third-party has reverse engineered the file to be able to read it correctly. Recently, Nikon started encrypting parts of its format to make it difficult for third party software to be able to process the file, Canon dropped support for its aging DSLR, the D30. RAW formats also get orphaned as camera makers go out of business - suddenly, you have no way to read all those pictures when you upgraded your computer. Best way to preserve a really important picture - print it using on of those archival inks!

A new initiative, OpenRAW.org promises to create an information source that will address these Digital Image Preservation issues by calling for an open format for exchanging RAW data. Adobe has already pitched the DNG (Digital Negative Specification), but no manufacturer has completely moved to it yet. The site has gotten of to a good start we hope they keep pushing for an open format not controlled by any one manufacturer that our pictures are stored in.