When you are browsing the Web and you see a highlighted and underlined word or phrase on a page, there is a good chance you are looking at a link. By clicking on a link, you can “jump” to a new Web page or a completely different Web site. While text links are typically blue and underlined, they can be any color and don’t have to be underlined.
Images can also serve as links to other Web pages. When you move the cursor over a link in a Web page, the arrow will turn into a little hand, letting you know that it is a link. The term “hypertext” comes from the way links can quickly send you to another Web destination.
So, Why are Links Blue?
Red and green are the colours most affected by colour-vision deficiency. Almost no one has a blue deficiency. Accordingly, nearly everyone can see blue, or, more accurately, almost everyone can distinguish blue as a colour different from others. It was pure good luck that the default colour of hyperlinks is blue with underlining.