What is a RAW photo?
When your digital camera saves a photo as a jpg, it does a lot of processing and compressing to the image data before it saves it. The point is to make it look as good as possible without taking up too much space.
A RAW photo is an image file with the raw image data of the photo sensor. This contains much more information than a processed jpeg. Since the RAW image hasn’t been processed to look it’s best, it often doesn’t look particularly pleasing. On the other hand, if you know how to edit RAW photos you can make them reveal much more than what’s visible in a jpg.
To learn about editing RAW photos, and see lots of before and after photos, read Sebastian de With's article in the Halide blog: