2.1.19 [CSS-Level2-2009] Section 5.11.2, The link pseudo-classes: :link and :visited


The specification states:

 User agents commonly display unvisited links differently from previously visited 
 ones. CSS provides the pseudo-classes ':link' and ':visited' to distinguish them:
 The :link pseudo-class applies for links that have not yet been visited. 
 The :visited pseudo-class applies once the link has been visited by the user.
 The two states are mutually exclusive.

Quirks Mode and IE7 Mode (All Versions)

The :link pseudo-class and the :visited pseudo-class are not mutually exclusive.