Underline links 
One of the first things beginning users learn is that links are underlined. Users don't read web pages but scan them for important information and words that are underlined stand out more. It isn't enough to simply use a different colour for a link. 8% of the white male population suffers from some form of colour-blindness and don't notice the difference in colour. A lot of sites aren't very consistent when it comes to underlining links: underlining some links and forgetting to underline others.

Only underline links 
Because users learn that links are underlined, they assume that everything that's underlined is also a link. Don't confuse your users and only underline links.

Use one colour for links and another colour for visited links 
To make sure users instantly recognize a link, it is best to put it in a different colour than your normal text colour. The standard colour for indicating a link is blue, which we strongly recommend. Should you choose a different colour, make sure it is a clearly legible colour that differs significantly from your regular text colour. To inform users about which links they have already visited and which ones they haven't yet, it is best to use a different colour for visited links. The standard colour for indicating a visited link is purple, which we strongly recommend. If you choose a different colour than blue for indicating a link, make sure you use a less bright colour for the visited links. To avoid confusing users, it is best to stick to one colour for indicating links and one colour for indicating visted links. An excellent example of this can be found on the site of the Australian newspaper The Age: all links are underlined and blue and visited links are purple.

Don't mess with the mouse pointer
Users aren't too happy with the fact that different web sites use different ways of indicating links. Of one thing however, the user is sure he can rely on it: when his mouse pointer turns into a hand, the item underneath the mouese pointer is a link. Respect this standard and don't use elements that cause the mouse pointer to turn into a hand when they're not links, like iLOOP does with the Flash game on its site. The blocks of the game seem clickable, but aren't. Misleading users like this confuses and frustrates them.

Clickable images 
If you use images on your site, you can make these clickable as well. The most important thing here is that you are consistent: users don't like it when some images are clickable and others aren't.

Els Aerts & Karl Gilis

A more in depth version of this article has appeared in Tips & Advies Online Ondernemen, year 5, number 20 (Belgium and the Netherlands).