Grammarly is an American cloud-based typing assistant that reviews spelling, grammar, punctuation, clarity, engagement, and delivery mistakes in English language text. It also detects plagiarism. It uses artificial intelligence to identify and search for an appropriate replacement for the located error. It also allows users to customize their style, tone, and context-specific language. It was launched in 2009 by Alex Shevchenko, Max Lytvyn, and Dmytro Lider. In 2018, Grammarly launched the beta version of its browser extension, which is optimized for Google Docs. As of 2022, it is available as a downloadable program for use with desktop applications, as a browser extension, and as a smartphone keyboard.