Single Sign-On (SSO) makes authentication easier by enabling users to sign into several applications using one set of credentials. SSO improves security by limiting password fatigue and the exposure to weak or duplicated passwords. SSO enhances user experience by removing the need for frequent logins. Nonetheless, correct implementation is essential to avoid security threats, including session hijacking or unauthorized access if a master credential is breached. Combining SSO with multi-factor authentication (MFA) and login activity monitoring can also increase security. Convenience and security need to be balanced by organizations to provide a smooth yet secure authentication experience.