The term "hyperlink" was coined in 1965 (or possibly 1964) by Ted Nelson at the start of Project Xanadu. Nelson had been inspired by "As We May Think", a popular 1945 essay by Vannevar Bush. In the essay, Bush described a microfilm-based machine (the Memex) in which one could link any two pages of information into a "trail" of related information, and then scroll back and forth among pages in a trail as if they were on a single microfilm reel.
It uses the HTML element "a" with the attribute "href" (HREF is an abbreviation for "Hypertext REFerence" and optionally also the attributes "title", "target", and "class" or "id":
< a href="URL" title="link title" target="link target" class="link class">link label< /a>
How hyperlinks work in HTML
A link from one domain to another is said to be outbound from its source anchor and inbound to its target.
The most common destination anchor is a URL used in the World Wide Web. This can refer to a document, e.g. a webpage, or other resource, or to a position in a webpage. The latter is achieved by means of an HTML element with a "name" or "id" attribute at that position of the HTML document. The URL of the position is the URL of the webpage with a fragment identifier — "#id attribute" — appended.