How are haiku's and limericks different?

Haikus and limericks are both poems. However, they differ in terms of length, rhyme scheme, and the presence of humor.A limerick poem consists of five lines. It follows the rhyme scheme of AABBA. This means that the first, second, and fifth lines rhyme, and the third and fourth lines rhyme. A limerick is usually comical. Some of the most famous limericks are nursery rhymes.

Ding, Dong, Bell is one example of a limerick nursery rhyme:
 
Ding, dong, bell; Kitty’s in the well.Who put her in?  Little Tommy Green.Who pulled her out?  Little Tommy Trout.What a naughty boy was that,To drown poor Pussy Cat.
 
A haiku, on the other hand, consists of five lines. While it does not rhyme, its lines do follow a specific syllable pattern. The first line always has five syllables, the second line has seven syllables, and the third line has five syllables. Haikus tend to be more serious than limericks. They are often about nature, and they are known for being direct and to the point.
 

The following haiku is written by a famous poet named Basho Matsuo:
 
An old silent pond...A frog jumps into the pond,splash! Silence again.
http://www.literarydevices.com/limerick/

https://poets.org/poems?field_form_tid=414