Frottole were quite simple and fun. They were often sung by small groups of singers. They were not contrapuntal, but they had a tune in the top part while the other singers sang chords to accompany the tune. Sometimes they might have been sung by a solo voice with a lute accompaniment.
The most famous composer of frottole was Bartolomeo Tromboncino. The great composer Josquin also composed frottole, although that is not what he called them. For example, there is a well-known one called El Grillo ( The Cricket) in which the singers try to sound like the chirping of a cricket in the grass.