GatsbyJS is a free and open-source framework based on React that helps developers build blazing-fast websites and apps. GatsbyJS was created by Kyle Mathews in 2015 and is now maintained by a team of developers. GatsbyJS is used by thousands of developers and companies around the world, including IBM, PayPal, and Airbnb. GatsbyJS is known for its speed, security, and ease of use. It uses modern web technologies like GraphQL and Webpack to deliver fast and efficient websites and apps. GatsbyJS is also highly customizable, with a large ecosystem of plugins and themes.