Why does Facebook have 500 million users? Five answers and some lessons for psychologists:

1) Because too many people are bored at work: If managers assessed employees for what they actually do, as opposed to the time they spend at work, they would not have to worry about them spending too much time on Facebook, let alone banning Facebook at work. Unfortunately, most people hate their jobs and are only "doing the hours" - they only care about their pay and have no ; they are badly managed and not well-utilised. It is therefore susprising that Facebook doesn't have more than 500 million users - most of the remaining people in the world hate their jobs, too (and, especially, they hate their bosses). If you are reading this at work, you may be one of those people - find our here.

2) Because too many people are unhappy about their love life: Some are single, others have made the wrong choice (or, at least, one that doesn't eliminate their desire to date other people). Facebook is not only an effective time-wasting device at work, it is also a hidden site. Indeed (if we believe The ) it was created to make-up for someone's romantic failures, and its membership grew exponentially when "relationship status" was added as a key profile feature. Only Facebook may know - if not, they will work it out soon - just how many people have managed to get in touch with their school sweethearts, and there's no better place for finding anyone anywhere in the world. If the internet transforms reality into information, Facebook is a huge digital meat market.

3) Because there are too many narcissists (and even more voyeurs) in this world: Psychologists have only recently come to realise that there are many psychopaths in the normal population. But Facebook confirms that there are even more , exhibitionistic people - why else would someone collect 1,000 "friends" and display 500 pictures of himself? This digitial showcase works well even for , introverted people (who would usually fail at attracting most people's in the world of real things). The reason why can do this is that there are even more people willing to spend hours looking at stranger's pictures and profiles: "Look, Pauline has only slept 5 hours (amazing!)".

4) Because one of the main human motives is the desire to "get along": And because of that, we can only predict that there will be many more Facebook users in the near future. The desire to connect with others clearly surpasses the limits of physical interaction. In Japan and Korea people are updating their Facebook profiles and contacting other users even while having dinner or socialising with their "analogue" peers. There are already clinics dedicated exclusively to treating Facebook-addicts (people who stopped going to school, college or work, and even stopped , just in order to spend more time on Facebook).

5) Because the other main motive is to "get ahead": And this is the very reason why Facebook exists. Its founder seemed unable to get along, so he decided to get ahead instead. Many entrepreneurs have similar characteristics: they are and anti-social, but hugely ambitious. Mark Zuckerberg couldn't get a date and barely had friends. So he decided to transform himself from techno-geek to mega-tycoon. He may not have increased his social skills, and still be a techno-geek, but his billions have probably helped him make some friends (not that he really cares about this anymore). The crucial lesson is that in achieving his personal , he also helped many others (500 million, but keep counting) satisfy their desire to "get ahead". People use Facebook to compete with each other: who's got more friends, and a more exciting life? This is the ultimate popularity contest.

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