Raw format is one of the formats that cameras can store data in. On almost all cameras (and phone cameras) you can store your pictures in jpg format.
Raw format is when pictures are stored exactly by the pixels (or dots) that make up the picture. This produces a larger file but loses no quality. However websites and many programs do not know how to use Raw format so the pictures have to be edited first in a data editing program and stored in a common format, most often jpg.
Jpg format is what most people shoot pictures in (on cheaper cameras it is the only choice). With jpg format the pictures are compressed in the files which make for smaller size files but some quality is lost. Pictures shot in RAW format can be stored as bigger jpg files and when printing large pictures work better. If you only print pictures to 4 X 6, then you may not see difference in jpg and Raw formats,
On higher end cameras you can choose to shoot Raw or jpg. Just remember that you can store less Raw images on a memory card, but the quality is better. Also Raw must be edited before most programs or photo services an use them.