The Limerick is an extremely old European rhyming structure that has been and still is extremely popular poetry. Some early Nursery Rhymes, like Hickory Dickory Dock, are Limericks.
1. I don’t really care who you are,
2. Or where you got that fancy sports car,
3. But I’m insightfully curious
4. As to whether you’re serious
5. About buying me drinks at that bar.
Lines 1, 2 and 5 rhyme.
Lines 3 and 4 rhyme.
The number of words and syllables in each line are not rigidly enforced.
The Limerick is perhaps the most famous type of poem in the world, rivaling only the Haiku. It is an easy rhyming scheme to learn and it flows very well.