My favorite food is raw onion. Have you ever tried it?
I like cooked onion a lot. I also like it's close relatives garlic, shallot, leaks and chives.
Yes, they are very similar. Do you know what gives them that strong characteristic "onion taste"? 
I'm not sure and no one really knows where its wild original form came from. 
Interesting. Do you know if onions will grow in the wild? Or were just developed by farmers? 
They grow wild as well. Most frequently it's a perennial but most farmers treat it as an annual. They usually harvest in it's first growing season