Single sign-on is a method that allows two web sites or applications to cooperate and authenticate a user into both systems while requiring only one login action by the

When the user logs into one system, that system lets the other system know the user is trusted. Each application maintains its own user profile. While it is sometimes possible to sync the two profiles between the two systems, it isn't required.

Single sign-on improves user experience and allows two separate systems to appear integrated.