Signing means writing your name in your own distinctive way on a document, letter, or other item to show that you created it, approved it, or agree to its terms. When you sign your name at the bottom of a birthday card, you're showing who wrote it. When your parents sign a permission slip, they're officially giving you permission to go on the field trip.

Your signature is uniquely yours, like a written fingerprint. Adults develop a consistent way of signing their name that becomes recognizable, and they use it on important papers like contracts, checks, and legal documents. Signing your name on a document can be a way to prove that you have read and agreed to something. While we now have digital signatures and electronic agreements, the act of signing remains important for many official purposes.

The word also refers to communicating using sign language, a complete language that uses hand shapes, movements, and facial expressions instead of spoken words. People who are deaf or hard of hearing often use sign language to communicate. Someone who knows American Sign Language (ASL) is signing when they use it to have a conversation. Sign languages are real, complex languages with their own grammar and structure. They're fully developed systems of communication with rules as sophisticated as any spoken language.