What are the similarities and differences between haiku tanka and senryu?

Haiku

Must be 17 syllables long

must be written in present tense

pure snapshot of topic

must focus on nature

indirect/direct mention of seasons

A haiku is a 1000 year old Japanese poem. They are written about nature. They must be 17 syllables long and written in present tense.

Ex:

Spring

Birds can come home

The world wakes from its long sleep

Snow turns to rain