What are the differences between 3/4 and 6/8 time signatures in music?

The main difference between 3/4 and 6/8 time signatures in music is the emphasis on the beats. In 3/4 time, there are three beats per measure, with the emphasis on the first beat. In 6/8 time, there are six beats per measure, with the emphasis on the first and fourth beats, creating a compound feel.