Use a social media account you already have to log in.
We permanently log you in - log in, and you'll stay logged-in until you log out.
You can only be logged into one computer - we'll automatically log you out of any others.
How we use third-party services
We don't write anything to your timeline. We ask for offline access so that you can log out of Facebook for your privacy. We'll ask when we'd suggest you post something on your wall.
We don't write to your Google+ account. We're asking for offline access so that you can log out of Google for your privacy. We'll ask when we'd suggest you share something with your circles.
We don't write to your LinkedIn account at all, and only use it for logging-in.
In all cases, we make a local copy of your basic profile information and copy your photograph (if you have one) to our servers. We update this information every time you log in. We use your email address as a unique identity. If you share the same email address on Google, Facebook or LinkedIn, we'll combine the information we're sent from each provider.