HTML (Hypertext Markup Language) is a standard markup language used to create web pages. It is the foundation of all websites and is used to structure content, add images, videos, and other multimedia elements, and create links between pages. HTML is a text-based language that uses tags to define the structure and content of a web page. These tags are enclosed in angle brackets and are used to indicate headings, paragraphs, lists, and other elements. HTML is a versatile language that can be used in conjunction with other web technologies such as CSS and JavaScript to create dynamic and interactive web pages.