Developed by Tim Berners-Lee in 1990, HTML is short for HyperText Markup Language and is a language used to create electronic documents, especially pages on the World Wide Web that contain connections called hyperlinks to other pages. Every web page you see on the Internet, including this one contains HTML code that helps format and show text and images in an easy to read format. Without HTML a browser would not know how to format a page and would only display plain text with no formatting that contained no links. Below is an example of a basic web page in HTML code.

In the very basic above example are the key parts to every web page. The first DOCType line describes what encoding the page uses. For most pages, unless they are using XML this line will work. Next, the HTML tag begins letting the browser know that HTML code is being used until it is terminated at the end of the page. Next, the head section contains header information about the page, which will almost always contain the title of the page and the meta tags. Finally, the body section is all content that is viewable on the browser. For example, all the text you see here is contained within the body tags.

HTML5 is the update made to HTML from HTML4 (XHTML follows a different version numbering scheme). It uses the same basic rules as HTML4, but adds some new tags and attributes which allow for better semantics and for dynamic elements that are activated using JavaScript. New elements include section, article, aside, header, hgroup, footer, nav, figure, figcaption, video, audio, track, embed (different usage), mark, progress, meter, time, ruby, rt, rp, bdi, wbr, canvas, command, details, datalist, keygen, and output. There are new input types for forms, which include tel, search, url, email, datetime, date, month, week, time, datetime-local, number, range, and color.

A number of elements have been removed due to being presentational elements, accessibility issues, or lack of use. These should no longer be used: basefont, big, center, font, strike, tt, frame, frameset, noframes, acronym, applet, isindex, and dir.

HTML5 also simplifies the doctype declaration. To declare a document as an HTML5 document, you only need the below tag for the doctype.