Authentication services are systems that verify the identity of users or devices before granting access to resources. They ensure that only authorized individuals can access sensitive information or perform specific actions. Common methods of authentication include passwords, biometrics, and security tokens. These services play a crucial role in cybersecurity by protecting data and systems from unauthorized access. They are often integrated into applications and networks, using protocols like OAuth and SAML to facilitate secure communication. By implementing robust authentication services, organizations can enhance their security posture and reduce the risk of data breaches.