Its is a possessive pronoun used to show ownership, but it is frequently confused with the contraction It’s.

It’s = It is or It has

If you can’t replace it's in the sentence with it is or it has, then you’ve got the wrong one!

  It’s her blue scarf. = It is her blue scarf.
  It’s been so long since we went. = It has been so long since we went.

It gets confusing because apostrophes are often used with nouns to show possession, as in Mike’s book or the dog’s bone.

However, the rule changes with the possessive its, which becomes a contraction when the apostrophe is added.

Examples:
  It’s hard to see its eyes through all of that fur.
  Its coarse brown fur tells us that it’s time for a bath.