What is HTML

HTML is a markup language that defines the structure of your content. HTML consists of a series of elements, which you use to enclose, or wrap, different parts of the content to make it appear a certain way, or act a certain way. The enclosing tags can make a word or image hyperlink to somewhere else, can italicize words, can make the font bigger or smaller, and so on.

Creates the structure for all web pages on the internet

A file ending in .html lets your browser know that you are coding in html

A brief History about HTML

The first version of HTML was written by Tim Berners-Lee in 1993. Since then, there have been many different versions of HTML. The most widely used version throughout the 2000's was HTML 4.01, which became an official standard in December 1999.

Another version, XHTML, was a rewrite of HTML as an XML language. XML is a standard markup language that is used to create other markup languages. Hundreds of XML languages are in use today, including GML (Geography Markup Language), MathML, MusicML, and RSS (Really Simple Syndication). Since each of these languages was written in a common language (XML), their content can easily be shared across applications. This makes XML potentially very powerful, and it's no surprise that the W3C would create an XML version of HTML (again, called XHTML). XHTML became an official standard in 2000, and was updated in 2002. XHTML is very similar to HTML, but has stricter rules. Strict rules are necessary for all XML languages, because without it, interoperability between applications would be impossible. You'll learn more about the differences between HTML and XHTML in Unit 2.

Most pages on the Web today were built using either HTML 4.01 or XHTML 1.0. However, in recent years, the W3C (in collaboration with another organization, the WHATWG), has been working on a brand new version of HTML, HTML5. Currently (2011), HTML5 is still a draft specification, and is not yet an official standard. However, it is already widely supported by browsers and other web-enabled devices, and is the way of the future. Therefore, HTML5 is the primary language taught in this course.

Examples of types of content that can be included on web pages

The following table shows a list of many of the types of content that can be added to web pages using different versions of HTML. In the early days of the Web, HTML (version 1.2) was very simple, but over time new versions were released that added more and more features. Still, if web designers wanted to add content or features that HTML didn't support, they would have to do so with non-standard proprietary technologies such as Adobe Flash. These technologies would require users to install browser plug-ins, and in some cases meant that certain users would be unable to access the content (for example, iPhones and iPads don't support Flash).

HTML5 has added support for many new features that will make it possible to do more with HTML, without relying on non-standard proprietary technologies.