Shooting in RAW isn't absolutely necessary - it all depends on you and what you want to do with your photos. If you like the jpg results that your camera produces, then that is great. If you want more tweaking/adjusting range then RAW might be for you. The RAW files have more data in them for the computer to work with. If I pull a jpg into LR I can still adjust colors, contrast, lights, darks, exposure, clarity, etc, but the degree to which I can adjust those elements will be greater in a RAW file.