Okay kiddo, so let's talk about Irkens! They are a fictional alien race from the cartoon show called "Invader Zim". They are little green guys (kind of like little green men from outer space in movies) who have big heads, skinny bodies, and big eyes.
Irkens are very smart and very good at building machines and technology. They are also very ambitious and a little bit bossy. They like to take over other planets and control everything on them.
The main character in "Invader Zim" is an Irken named Zim. He was sent to Earth to conquer it, but he's not very good at it because he's not very smart and he doesn't really understand humans.
So to summarize, Irkens are a race of tiny, green, intelligent aliens who like to build things and take over planets. And Zim is an Irken who is not very good at taking over Earth.