It's happy to have its tail.

A coworker asked me the other day about the difference between "its" and "it's." He was stuck and he needed a knock on the noggin to remember. Here is what I told him:

It's is a contraction. It means: "It is."

Its is a possessive, which is why these words throw us, right? Possessives generally have an apostrophe. John's cat. The boys' lunches. The children's playground.

Remember this: The cat played with its tail. It's happy to have its tail.