Often Web pages contain Hyperlinks, i.e references to a document or a specific element within a document. The effect of following a hyperlink may vary with the hypertext system and may sometimes depend on the link itself; for instance, on the World Wide Web, most hyperlinks cause the target document to replace the document being displayed, but some are marked to cause the target document to open in a new window or tab.
HTML is written in the form of HTML elements consisting of tags, enclosed in angle brackets (like <html>), within the web page content. HTML tags normally come in pairs like <h1> and </h1>. The first tag in a pair is the start tag, the second tag is the end tag (they are also called opening tags and closing tags). In between these tags web designers can add text, tables, images, etc..
The purpose of a web browser is to read HTML documents and compose them into visible or audible web pages. The browser does not display the HTML tags, but uses the tags to interpret the content of the page.
A more restrictive format of HTML is called XHTML or eXtensible HyperText Markup Language, Because XHTML documents need to be well-formed, they can be parsed using standard XML parsers—unlike HTML, which requires a lenient HTML-specific parser.
An Introduction to HTML
HTML or Hyper Text Markup Language is, according to the definition, a Markup Language which consists of a set of Markup Tags used to describe a Web Page
An HTML tag or HTML Elements is a keyword surrounded by angle brackets like <html>
Usually HTML tags normally come in pairs like <b> and </b> with a start tag and an end tag, sometimes called opening tags and closing tags.
Web Pages are described by HTML Documents which contain HTML Tags and plain text. Tags are used to described how the text must be displayed by the Web Browser
You can read a more detailed introduction to HTML on the W3Schools.com website.
Another useful resource is HTML Code Tutorial
