Single Sign-On (SSO) is a login method where one set of credentials, managed by a central identity provider, grants access to many different applications. Instead of remembering a separate password for email, your CRM, your design tools and your support desk, a person logs in once and each app trusts that single sign-in to let them through.
Think of a festival wristband. You show your ID once at the gate, get a wristband, and after that you walk into every stage and bar by flashing the band rather than proving your identity again and again. SSO is that wristband for your software: prove who you are once, then move between tools without re-entering passwords.
Under the hood SSO relies on a trusted identity provider and standards like SAML or OpenID Connect, often built on OAuth. Because the login is centralized, you can attach strong authentication and require MFA in one place, and you can instantly cut off someone’s access to every app the moment they leave the company.
The flip side is that the identity provider becomes a single point of failure. If it goes down or the central account is compromised, a lot rides on that one door, which is exactly why teams pair SSO with conditional access rules that check device, location and risk before letting a session through. A new hire benefits most: on day one they get access to the whole stack at once, and on their last day a single switch revokes it everywhere.
At TopDevs we wire client apps into the identity provider they already use, so their team gets one secure login and IT keeps clean control over who can reach what.
