Let's start with a quick definition.
RAW is an uncompressed file format that captures all data recorded by the sensor of your camera. It's like negative in film photography, the RAW file is a negative in digital photography.
When I first started shooting in RAW, it changed dramatically the quality of my work. I've never shot in JPG since.
Why You should be shooting in RAW?
Here are my 5 Reasons :
1. Quality and better details.
2. White Balance correction.
3. Exposure correction.
4. Sharpening and noise reduction.
5. Better Workflow, you can always back your original RAW files.