What is the difference between rhythm guitar and bass guitar?

I play guitar. The most obvious reason is that the bass guitar is that gives the song backing so it sounds more full. The rhythm guitar gives more of treble sound but it is more versatile and can give off a bass sound too. Plus the rhythm guitar is more upfront while the bass guitar lurks in the background and fills in to give it a fuller sound. I mean unless you turn the bass up all the way on your stereo you don't really notice unless they play with a pick or if you had good ears or it's a quiet song you can hear the "plunk." Anyways, it's filler, but that's just my answer. It's rhythm and filler. The Bass guitar, along with the bass drum, adds the foundation, or bottom to the song. If you tap your foot to the music, you are tapping to that foundation. The rhythm guitar, fills in the holes, aka filling in the music between the beats of the drums, and the fullness of the bass. Together they form the rhythm section to the song.