Single Sign-On (SSO)
One set of credentials gives a user access to multiple applications, without signing in separately to each one.
Single Sign-On lets a user authenticate once with an identity provider and access every connected application afterward without re-entering credentials. The identity provider issues a token confirming who the user is; each application trusts that token instead of asking for a password of its own.
The security benefit isn’t just convenience: fewer passwords means fewer weak or reused passwords, and a single, properly-secured credential is easier to protect than a dozen scattered ones — especially when it’s backed by MFA.
SSO is usually implemented through standards like SAML or OpenID Connect, and works alongside Conditional Access to control the conditions under which that single sign-in is trusted.