8. Hypertext Markup Language (HTML)

HTML is a computer language devised to allow website creation. These websites can then be viewed by anyone else connected to the Internet. It is relatively easy to learn, with the basics being accessible to most people in one sitting; and quite powerful in what it allows you to create. It is constantly undergoing revision and evolution to meet the demands and requirements of the growing Internet audience under the direction of the »W3C, the organisation charged with designing and maintaining the language.

The definition of HTML is Hypertext Markup Language. Hypertext is the method by which you move around on the web — by clicking on special text called hyperlinks, which bring you to the next page. The fact that it is hyper just means it is not linear — i.e. you can go to any place on the Internet whenever you want by clicking on links — there is no set order to do things in. Markup is what HTML tags do to the text inside them. They mark it as a certain type of text (italicized text, for example). HTML is a Language, as it has code words and syntax like any other language.

It's what all web pages need to present anything in the browser (even a Flash-only site will need a little HTML to get started). It’s not a programming language, but markup; it describes what should go on the page. It's not like using a Word processor though states that this is the page's main heading. However, the browser can render this as it sees fit. HTML does provide ways of changing colors and styles, but it's best to use Cascading Style Sheets (CSS) for that.

CSS is typically used to create presentational effects for semantic HTML. With CSS, a designer can create the content with the appropriate, semantic markup and then use CSS to alter the appearance of their markup. The idea is that strictly presentational elements (such as italics or bold lettering) should not be used in the code and that any use of presentational elements should have some meaning attached to it, such as a citation.

HTML defines several data types for element content, such as script data and style sheet data, and a plethora of types for attribute values, including IDs, names, URIs, numbers, units of length, languages, media descriptors, colors, character encodings, dates and times, and so on. All of these data types are specializations of character data.