The difference is, the image quality and colours when editing in Photoshop or Lightroom. It does take more room if you have set raw file format.I am a beginner and for almost 4 years I use JPG . I dont really understand the difference of JPG and RAW. I only know JPG's file size is less than RAW.
But now after I joined this group, I changed my camera setting to RAW. In case, I spot a good object and I don't want to lose the quality.