HTML is a markup language used to structure and present content on the web. It was invented by Tim Berners-Lee in 1990 and standardized by the W3C. Popular HTML editors include Notepad++, Sublime Text, and Brackets. Common web browsers that can display HTML pages are Google Chrome, Internet Explorer, Firefox, Safari, and Opera. HTML uses tags to define elements like headings, paragraphs, and lists, which are the building blocks of web pages.