Logging out hotmail/outlook windows 8

I have just bought a new laptop loaded with Windows 8. When getting it started, I was prompted to enter my name and an email address. Foolishly thinking this was just for future news from Microsoft, etc, I did this and entered my Hotmail address. I was surprised that once the machine was up and running, all the emails in my intray were visible for anyone using the computer to read by just clicking on 'email'. There is no apparent log-off button as there was in Windows 7. How do I log off to prevent anyone else reading my mail, and how do I create private Hotmail accounts for my wife and daughter that they also can log out of and keep their privacy? I am sure that this must be easy to do, as surely Microsoft would never have made such a basic error!