As a programmer, Swartz helped develop the web feed format RSS;[1] the technical architecture for Creative Commons, an organization dedicated to creating copyright licenses;[1] and the Python website framework web.py.

Swartz helped define the syntax of lightweight markup language format Markdown, and was a co-owner of the social news aggregation website Reddit and contributed to its development until he left the company in 2007.

[31] The site won the ArsDigita Prize, given to young people who create "useful, educational, and collaborative" noncommercial websites and led to early recognition of Swartz's nascent talent in coding.

[36] During Swartz's first year at Stanford, he applied to Y Combinator's first Summer Founders Program, proposing to work on a startup called Infogami, a flexible content management system designed to create rich and visually interesting websites[37] or a form of wiki for structured data.

[52] The Huffington Post characterized his actions this way: "Swartz downloaded public court documents from the PACER system in an effort to make them available outside of the expensive service.

"[54] Malamud appealed to fellow activists, urging them to visit one of 17 libraries conducting a free trial of the PACER system, download court documents, and send them to him for public distribution.

[54] After reading Malamud's call for action,[54] Swartz used a Perl computer script running on Amazon cloud servers to download the documents, using credentials belonging to a Sacramento library.

[63] In 2010,[64] Swartz co-founded Demand Progress,[65] a political advocacy group that organizes people online to "take action by contacting Congress and other leaders, funding pressure tactics, and spreading the word" about civil liberties, government reform, and other issues.

I called all my friends, and we stayed up all night setting up a website for this new group, Demand Progress, with an online petition opposing this noxious bill.... We [got] ... 300,000 signers.... We met with the staff of members of Congress and pleaded with them.... And then it passed unanimously.... And then, suddenly, the process stopped.

[74] In 2006, Swartz wrote an analysis of how Wikipedia articles are written, and concluded that the bulk of its content came from tens of thousands of occasional contributors, or "outsiders," each of whom made few other contributions to the site, while a core group of 500 to 1,000 regular editors tended to correct spelling and other formatting errors.

"[75][76] His conclusions, based on the analysis of edit histories of several randomly selected articles, contradicted the opinion of Wikipedia co-founder Jimmy Wales, who believed the core group of regular editors provided most of the content while thousands of others contributed to formatting issues.

[77][78] According to state and federal authorities, Swartz used JSTOR, a digital repository,[79] to download a large number[note 2] of academic journal articles through MIT's computer network over the course of a few weeks in late 2010 and early 2011.

[16] On September 25, 2010, the IP address 18.55.6.215, part of the MIT network, began sending hundreds of PDF download requests per minute to the JSTOR website, enough to slow the site's performance.

[90] On the night of January 6, 2011, Swartz was arrested near the Harvard campus by MIT Police and a Secret Service agent, and arraigned in Cambridge District Court on two state charges of breaking and entering with intent to commit a felony.

[102] According to a spokesperson for the Middlesex County prosecutor, this was done to avoid impeding a federal prosecution headed by Stephen P. Heymann, supported by evidence provided by Secret Service agent Michael S.

[103][102] On September 12, 2012, federal prosecutors filed a superseding indictment adding nine more felony counts, increasing Swartz's maximum criminal exposure to 50 years of imprisonment and $1 million in fines.

[110][111] On December 4, 2013, due to a Freedom of Information Act suit by the investigations editor of Wired magazine, several documents related to the case were released by the Secret Service, including a video of Swartz entering the MIT network closet.

[121] Swartz's family and his partner created a memorial website on which they issued a statement, saying: "He used his prodigious skills as a programmer and technologist not to enrich himself but to make the Internet and the world a fairer, better place.

On January 19, hundreds attended a memorial at the Cooper Union, speakers at which included Taren Stinebrickner-Kauffman, open source advocate Doc Searls, Creative Commons' Glenn Otis Brown, journalist Quinn Norton, Roy Singham of ThoughtWorks, and David Segal of Demand Progress.

[129][130][131] On January 24, there was a memorial at the Internet Archive headquarters in San Francisco (video[132]) with speakers including Stinebrickner-Kauffman, Alex Stamos, Brewster Kahle,[133] Peter Eckersley, and Carl Malamud.

[141][142] Carmen M. Ortiz, then U.S. Attorney for the District of Massachusetts, said in a statement: "As a parent and a sister, I can only imagine the pain felt by the family and friends of Aaron Swartz, […] I must, however, make clear that this office's conduct was appropriate in bringing and handling this case.

"[146] This comment triggered some criticism; Esquire writer Charlie Pierce replied, "the glibness with which her husband and her defenders toss off a 'mere' six months in federal prison, low-security or not, is a further indication that something is seriously out of whack with the way our prosecutors think these days.

[160][161][162] Reuters news agency called Swartz "an online icon" who "help[ed] to make a virtual mountain of information freely available to the public, including an estimated 19 million pages of federal court documents.

"[163] The Associated Press (AP) reported that Swartz's case "highlights society's uncertain, evolving view of how to treat people who break into computer systems and share data not to enrich themselves, but to make it available to others,"[68] and that JSTOR's lawyer, former U.S. Attorney for the Southern District of New York Mary Jo White, had asked the lead prosecutor to drop the charges.

[174][175] A hacker downloaded "hundreds of thousands" of scientific-journal articles from a Swiss publisher's website and republished them on the open Web in Swartz's honor a week before the first anniversary of his death.

[185][186][187] Preliminary topics worked on at the 2013 Aaron Swartz Hackathon[188] were privacy and software tools, transparency, activism, access, legal fixes and a low-cost book scanner.

[211] Speaking at a memorial for Swartz on Capitol Hill, Issa saidUltimately, knowledge belongs to all the people of the world.... Aaron understood that.... Our copyright laws were created for the purpose of promoting useful works, not hiding them.Massachusetts Democratic Senator Elizabeth Warren issued a statement saying "[Aaron's] advocacy for Internet freedom, social justice, and Wall Street reform demonstrated ... the power of his ideas ..."[212] In a letter to Attorney General Eric Holder,[213] Texas Republican Senator John Cornyn asked, "On what basis did the U.S. Attorney for the District of Massachusetts conclude that her office's conduct was 'appropriate'?"

[212] On January 28, 2013, Issa and ranking committee member Elijah Cummings published a letter to U.S. Attorney General Holder, questioning why federal prosecutors had filed the superseding indictment.

[47][219][220] Congressional staffers left this briefing believing that prosecutors thought Swartz had to be convicted of a felony carrying at least a short prison sentence in order to justify having filed the case against him in the first place.

Past speakers include Chelsea Manning, Barrett Brown, Trevor Timm from Freedom of the Press Foundation, Cory Doctorow, Cindy Cohn, Jason Leopold, and Brewster Kahle.