An anchor can have for different pseudo-classes:

css
/* unvisited link */
a:link {}
/* visited link */
a:visited {}
/* mouse over link */
a:hover {}
/* selected link */
a:active {}

• a:hover must come after a:link and a:visited in the CSS definition in order to be effective!!
• a:active must come after a:hover in the CSS definition in order to be effective!!
• Pseudo-class names are not case-sensitive.