When I “check in” a screen appears that asks if I want to share on Facebook or Twitter. What does that mean?
That is an optional feature on foursquare or other sites that allow you to check in when you are in a sponsored location. They ask everybody if they want to post a link to their check in on their Facebook wall or Twitter news feed. If you check yes, then you would have to give your email and password to these two accounts, so you definitely do not have to do it. It gives this site some info you do not need to give and it takes time.
