Authentication is the process of verifying the identity of a user or system. It ensures that the person or device trying to access information is who they claim to be. Common methods of authentication include using passwords, biometric data like fingerprints, or security tokens. This step is crucial for protecting sensitive data and maintaining security in various applications, such as online banking or social media. When you log into your account, the system checks your credentials against stored information. If they match, you gain access; if not, you are denied. This verification process helps safeguard your personal information and keeps unauthorized users out of your accounts.