A headless chicken is a sexual maneuver involving a man and a woman.
The man proceeds to insert his head inside the woman's vagina meanwhile standing up.
He should then place his thumbs under his armpits and then flap his arms while running around in a random path thus simulating the actions of the ever so popular poultry.
This should be done until the man runs out of air.
Facebook is effectively an online database of people where people voluntarily upload all their personal information so that random people they have only met once, formally known as "friends", can track whatever they are doing for the rest of their lives.
This act of offering up personal information also equips Facebook founder, Mark Zuckerberg, with near infinite power as he stores all the information, including conversations, permanently in order to make a huge profit through manipulation and as such can be compared to the famous fictional oligarch Big Brother from the book 1984, written by George Orwell.
Naive friend: Hey guess who has access to all my personal information that I protested vehemently against the police and government keeping yet am ok with doing it myself because I'm a conformist and Facebook is awesome?
Realist friend: Lord Zuckerberg and that random guy you met at a party once who turned out to be paedophile and mass murderer.