Code.org is a non-profit organization and eponymous website led by Hadi and Ali Partovi that aims to encourage people, particularly school students in the United States, to learn computer science. The website includes free coding lessons and the initiative also targets schools in an attempt to encourage them to include more computer science classes in the curriculum. On December 9, 2013, they launched the Hour of Code nationwide to promote computer science during Computer Science Education Week through December 15, 2013.

During Computer Science Education Week from December 9 to December 15, 2013, Code.org launched the "Hour of Code Challenge" on its website to teach computer science to school students, enticing them to complete short programming tutorials. The Hour of Code involved getting people to write short snippets of code to achieve pre-specified goals using Blockly, a visual programming language of a similar flavor as Logo. The initiative had been announced about two months in advance and at the time of launch, the initiative was supported by former United States President Barack Obama as well as executives from technology companies such as Microsoft and Apple Inc. It was also supported by educational online learning platforms such as Khan Academy. About 20 million people participated and over 600 million lines of code had been written. The Hour of Code also offered participation gifts to some of the schools involved, such as a set of fifty laptops or a conference call with one a tech "luminary" like Gates or Dorsey. The crowdfunding effort for Hour of Code received the highest amount of funding ever raised on Indiegogo. By October 2014, about forty million students had taken the Hour of Code class, and a second Hour of Code was held in December 2014. That year, locations for Hour of Code lessons included Apple retail stores.