what is the keep me logged in functionality in rails?

I am creating a login form where username , passowrd and one checkboxed with label " 开发者_运维知识库keep me logged in Until I log out " i want to know is it a basic functionality? what happened if i checked the checkbox and vice-versa? i am using.

Any help is appreciated.

The "keep me logged in" feature usually mean the user's connection won't be closed at the end of the session (when the browser is closed).
It mean the user's credentials aren't stored in a session but on a cookie.

However that's not a basic rails feature. Rails doesn't includes any authentication feature.
You must develop your own authentication plugin or use an open source one, like devise, authlogic or clearance