HTML or Hypertext Markup Language is the basic language used in the creation of web pages. Hypertext refers to text stored in electronic format that can be crosslinked, and markup language refers to a set of instructions for displaying information. When HTML was initially developed in the early 1990s, web pages consisted primarily of text and the first version of HTML was primarily concerned with displaying text. However, HTML has evolved over the years and now HTML can instruct the browser not only how to display text information but such component parts of a webpage as: graphics, multimedia, scripts, etc.
In the early days of web design there were no standardized rules for HTML, and different browsers would display web pages differently. In addition, Netscape and Explorer, the two most popular web browsers at the time, started creating their own versions of HTML, meaning that a webpage designed for Netscape might not display properly in Explorer, and visa versa. To resolve these problems, the World Wide Web Consortium was founded in 1994. Its goal is to set standards that all those involved in web site creation could follow, and that would be displayed similarly no matter which browser was used. The World Wide Web Consortium was instrumental in creating and updating HTML versions, as web pages grew more sophisticated. HTML versions have changed with the times, starting with HTML 2.0 in 1995 (there was no HTML 1.0 designation even though HTML had been in use for several years before HTML 2.0) to the most current version of HTML 5.0
Another key development that impacted HTML was the creation of XML, or Extensible Markup Language, which is basically a standard for the creation of Markup Languages, stricter than the standards followed by HTML. To create a version of HMTL to conform to XML standards, the World Wide Web Consortium developed XHTML, which is basically HTML with stricter guidelines.
HTML is a series of text instructions that instruct a web browser how to display a web page, as mentioned above, and therefore a web page can theoretically be designed with a text editor, such as Notepad or Word. However, in practice it is common to use software designed specifically for web page creation, such as Dreamweaver. With this software it is possible in theory to design an advanced website without any familiarity with HTML.
The basic building block of HTML is the tag. An html tag is a command used to tell a browser how to display a part of the webpage. While there are literally hundreds of html tags, every webpage will generally include the following: <html>, <head>, <title> and <body>. In addition, most web pages will include at least one paragraph, or <p> tag.
Some other common tags include:
| HTML Tag | Name | Description |
|---|---|---|
| <h>, </h> | Heading | Heading tags display text in large bold letters, with the size ranging from 1 to 6, with 1 being the largest. The format is <h1>Heading</h> |
| <li>, </li> | List Item | A list item. Can be combined with the <ol> or <ul> tag for an ordered or unordered list. |
| <b>, </b> | Bold | Displays text enclosed within in bold lettering. |
| <i>, </i> | Italic | Displays text enclosed with in italic lettering. |
| <img>, no closing tag | Image | Used as a stand alone tag to display an image inside a web page. |
| <a>, no closing tag | Anchor | Use to create hyperlinks to other web pages within the same site or on other sites. |
| <br />, no closing tag | Break | Creates a line break without a space, unlike the paragraph tag. |
| <div>, </div> | Division | A generic tag used for formatting with style sheets. |
The html tag instructs the browser to expect an html document, in other words a web page. The head and title tags are used to indicate text that will be displayed at the top of the browser window, and the body tag indicates text that will be displayed in the main browser window. The paragraph tag is used to separate the text into paragraphs.
Most HTML tags consist of two parts: an opening tag and a closing tag. Tags are enclosed by the brackets as shown in the examples above, and the closing bracket includes a slash; /. For example, the opening tag for title is <title>, and the closing tag is </title>. The </title> closing tag, for example, tells the browser the title is ended. After creating the web page, the file is saved with a name, using the .htm or html extension.
Of course this is just the beginning. HTML can be used to modify fonts, create headers, insert images, create hyperlinks, etc. Text, images, etc. can be formatted using Cascading Style Sheets, which are separate pages used to store formatting information and referenced by the HTML code. HTML can be combined with Javascript to create dynamic text effects. The possibilities are endless
Newer websites generally conform to the standards of XHTML. While similar to HTML, XHTML imposes stricter rules. A couple of key differences are:
- In XHTML all tags must be lowercase. In HTML, it doesn’t matter.
- Closing tags are required in XHTML. They were also standard in HTML, but pages would often display correctly if the closing tags were omitted.
Even though XHTML is the standard now, there are still quite a few webpages written in HTML. As newer versions of browsers are developed, the older versions of HTML may no longer be supported. It is therefore important that for those of us who learned web page design using HTML to update our skills (and our webpages!), and for newcomers to learn XHTML from beginning. For more information on HTML basics, check out this html article for a tutorial on html basics from w3schools.