Jack Dorsey, Dick Costolo, Biz Stone and Evan Williams are fairly well known names at Twitter.

But there are a lot of people working hard behind the scenes to make Twitter the multi-billion-dollar company it is today.

Here are some people who play integral roles at Twitter who don't get enough recognition.

Dom Hoffman and Rus Yusupov, @dhof and @rus

Title: CEO and General Manager of Vine; Creative Director of Vine

When they joined Twitter: October 2012

Why they are significant: Rus and Dom sold Vine to Twitter before their video sharing app even launched. Since then, the app has exploded to 40 million users and it's a big part of Twitter's media sharing plan.

Chloe Sladden, @ChloeS

Title: Head of Media 

When she joined Twitter: Feb. 2012

Why she is significant: Sladden has been named one of the most "influential women in tech" and she heads up all media relationships for Twitter. When you see tweets at the bottom of TV shows, like The Bachelorette, the presidential debates, or the VMAs, that's Sladden's doing.

Vijaya Gadde, @Vijaya

Title: General Counsel

When she joined Twitter: July 2011 as Director of Legal 

Why she is significant: In August, Gadde took Alex MacGillivry's role as General Counsel of Twitter. She specializes in corporate and securities law, which will be important when the company goes public.

Katie Jacobs Stanton, @KatieS

Title: Vice President of International Market Development

When she joined Twitter: August 2010

Why she is significant: Stanton has been named one of Forbes' most powerful women. She was named Special Adviser to the Office of Innovation at the U.S. Department of State and President Obama previously appointed her Director of Citizen Participation. Staton helped Twitter open offices in Japan, Brazil and Europe. She's being moved to abroad to help aid international expansion.

See the rest of the story at Business Insider

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