LONDON (CNNMoney.com) -- Twitter said Tuesday that it will start featuring ads as part of the company's effort to turn its popularity into profit.
Twitter co-founder Biz Stone unveiled the new advertising platform, called Promoted Tweets, on the company's blog.
"This announcement is a long time coming," said Stone in the announcement.
How Twitter plans to make money has been a question that, until now, the company has been reticent about.
Twitter allows users to post 140-character entries called "tweets."
Now when users conduct a search on the site, tweets paid for by Twitter's advertising partners will be displayed at the top of the search results page.
Other than carrying a label that signals they are being paid for by an advertiser, the promoted posts will look like a regular tweet.
As recently as last September, Stone had said it would be "awhile" before Twitter displayed ads on its Web site.
The company has taken heat for not revealling its business plan, but Stone was quick to poke fun at himself.
"When your name is Biz and you're a co-founder of Twitter, it also means putting yourself at the mercy of folks like Stephen Colbert, who hit home runs wtih lines like, 'So I assume that Biz in Biz Stone does not stand for Business model.'"
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