Have you ever noticed some innocent guy or a girl sharing a crappy video or links in their Facebook profile? This often leads to curiosity and make you too visit the page. Now you are gone! Your friends will get notified that you are watching *that* video in their home page. Here once you proceed into the page, without your knowledge, you will be tricked to share the link to the page in your profile.
Let's look at some such tricks played to make you share the link to the page/video or make you like it, without even knowing that.
In this page, once you click 'play', a link to the page will be shared on your profile. It is actually a 'share' and 'like' options engineered to have a video look!
Here, both the 'Confirm' and 'Cancel' work as the 'share'.
If you really want to see what is inside the video, just log out and try to click the link. Sometimes it will ask you to login, and sometimes it will try to redirect you to some crappy survey, which will lead you to a no-where-zone.
Facebook has a rigid censor policy. It doesn't allow any 18+ material in it. Don't be fooled by such claims, and avoid further embarrassment of sharing all the craps over your profile. These tricks are, of course used to spread rumors and hoaxes too.
A better option would be, go elsewhere anonymous and try, not in a social networking site, where you have proven your identity. Google is always your friend, and public image matters!