An OAuth2 token is a digital credential used in the OAuth 2.0 authorization framework. It allows applications to securely access a user's resources on another service without needing to know the user's password. Instead, users grant limited access permissions, and the application receives a token to access specific resources. These tokens are time-limited and can be revoked, enhancing security. OAuth2 tokens are commonly used in web and mobile applications to enable features like single sign-on and delegated access to APIs, helping protect user credentials while ensuring seamless integration between services.