A "proof checker" is a tool that helps you make sure your work is right. It looks at your work, like an essay or paper that you wrote, and checks it for any mistakes. It can also check your spelling, grammar, and punctuation. Proof checkers can be found online, but they can also be found in writing programs like Microsoft Word. Using a proof checker can help you make sure your work is error-free, so you can turn in the best work possible.