How do online social networks make a profit?

[M S]

I am curious to know how social networks make a profit, by advertising or by what means

[stanggt3]

advertisers

[merrilyn]

I believe most of the profit has to do with selling ad space to advertisers, so if you're already feeling jovial while chatting or browsing pictures, you'll click on their ad bar and go to their site (and hopefully buy). That's what allows a lot of free webhosting as well: Joe Schmoe can have his own website for free if he signs up with a company, and that company allows other advertisers a little place on Joe's individual site. (thus giving Joe the profit of a free site, and the company the ad profits which in turn partially fund the costs of hosting).
Social dating sites like Match.com and EHarmony.com of course charge membership fees, and I think they probably sell ad space too. It seems like those little sidebars are everywhere.

[Christina9999]

Advertising and the personal information you provide gets sold to companies and political parties.

[Mark Welch]

They don't.

This is a crucial fact to realize: despite multi-billion dollar sales of "social networking web site" companies, none of these companies makes a profit.

Revenue comes primarily through advertising, including "sponsorships." I am not aware of any "information sales" (such as selling your registration data to companies or political parties) but that's certainly possible, if permitted by the company's privacy policy.

[Sharing Mind]

all free service profit oriented sites earn money from advertising. but the requirement is to have tons of traffic daily. advertiser will come in when they find any sites that has high traffic volume. internet is about competition and better services. so don't expect to earn money just by making one. 5-10% of these site would make money. it is the nature of human beings, stay with the best. all the not so best will die down and perish.