title: User login/session system description
body: <p>I'm building my first web app, and I've got all these crazy ideas on ways I could handle things like logins/sessions, but I was wondering if anyone has written a really good, thorough description of how logins/sessions work. I've seen tutorials, but I want to know if theres something more abstract that gives the reader a more general idea of how the whole process is handled. My web app is in ruby/sinatra if that's relevant.</p>