Human–animal communication is when people and animals talk to each other. Even though people can't understand exactly what animals are saying, animals still try to talk to us. Animals might make a sound, move their body in a certain way, or give us a certain look that they want us to understand. For example, a dog might bark when it wants to go outside or sits at the door when it wants to be let in. People can learn to understand these signals and can then talk back.