Aaron Swartz, one of the early builders of popular website Reddit, was found dead in New York on Friday. He was 26.
Swartz committed suicide, apparently by hanging, his uncle, Michael Wolf, said. His girlfriend found his body.
The programmer and Internet activist co-authored the RSS 1.0 specification, which is widely used for publishing news stories.
Swartz also started the company Infogami which merged with Reddit in 2006 and he is largely considered a co-founder of the popular news site.
Users on Reddit can submit content and also vote "up" or "down" to rank the posts.
Reddit was sold to giant publisher Conde Nast, which owns Wired, among other magazines. When Swartz and his team moved out to San Francisco to begin working at the offices or Wired News, he blogged about how he was "miserable."
"I couldn't stand San Francisco. I couldn't stand office life. I couldn't stand Wired. I took a long Christmas vacation. I got sick. I thought of suicide," he wrote in his blog. "I ran from the police. And when I got back on Monday morning, I was asked to resign."
Swartz is also the founder of Demand Progress, which launched the campaign against the Internet censorship bills (SOPA/PIPA) and now has over a million members.
In 2011, the Internet activist was indicted for illegally downloading 4 million academic journals from JSTOR through the MIT network with the intent to provide free public access. He returned the hard drives with the documents and pleaded not guilty in court on Sept. 24, 2012.
Swartz was still facing charges in the JSTOR case.
JSTOR, a digital library of academic journals, books and primary sources, recently decided to allow free limited access to its archives.
Swartz's mother released a statement on Ycominbator.com, saying, "Thank you all for your kind words and thoughts. Aaron has been depressed about his case/upcoming trial, but we had no idea what he was going through was this painful.
"Aaron was a terrific young man. He contributed a lot to the world in his short life and I regret the loss of all the things he had yet to accomplish. As you can imagine, we all miss him dearly. The grief is unfathomable."
Commenters have left tributes, remembering Swartz for all his accomplishments.
"I am so sorry for your loss. Your son was a genius and a generous person true to his beliefs -- the rarest sort. You should always be proud of him," said one commenter.