A contraction is a short way of writing two words together.
Some of the letters are left out. An apostrophe (') takes the place of the missing letters.
Some contractions are formed by joining pronouns and verbs.
I would've liked to see the shark at the aquarium.
would + have = would've
You're feeling happy and wonderful today!
You + are = You're
It's going to be windy today.
It + is = It's