What is the definition of it ? 

The answer only yields more questions.  But whether you're looking for it or I.T., you've come to the right place.		   information technology careers in USA
   

The definition of "it" as a pronoun:
   The definition of "I.T." the abbreviation:    

"it" can mean almost anything, it turns out.  Even you can be it, especially if it's recess and you're slow. 

"definition of it as a pronounit" is most often used as a pronoun, as the animal or thing previously mentioned or under discussion: as a unisex personal pronoun in the third person singular: like you might say "it ate all the taxis" of a giant monster rat, because you don't know if "it" is a girl or a boy giant monster rat.  (That's why you can't say "she ate all the taxis")

"it" is also used as the subject of an impersonal verb without reference to any actor: like you might say "it is stinky in here."  What is?  "it" is.

it as a subject"it" can be the grammatical subject of a clause where the actual subject is another clause or phrase: like you might say  "it is unfortunate you didn't pay me back before I came over here."  What is unfortunate?  "it" is.

Sometimes "it" will be an object of uncertain sense in expressions you blurt out before committing a felony: like "let him have it" or "you're going to get it."

The flipside of that dark "it" is the good news "it", where "it" becomes the "it" in "it's all good."  What is all good?  "it" is.

Finally, informally you might use the word "it" as a predicate pronoun referring to something you consider the end, or perfect: like Michael Jackson's "this is it."

 
"I.T." the abbreviation stands for information technology, and it is not as exciting as the left column.

information technology

If plugging cables into ports until it works turns you on, then I.T. is for you.

If spending your lunch hour in a sterile break room eating microwaved hot pockets from a vending machine sounds fun, then maybe I.T. really is for you.