Text hyperlinks should be clearly distinguishable from normal text.

The blue links delivered the longest visit duration, lowest bounce rate and the highest goal conversion.

Seems like Microsoft did a good job of subliminally training us over the years with the classic blue link color.

So why has the blue underline proved so long-lived? A clue lies in the fact that, according to Jakob Nielsen, �life is too short to click on things you do not understand.� He is right; links have to be instantly recognizable as such to be usable. Simply put, links lack �affordance�. It is impossible to figure out their function from their appearance. You have to know through experience or learning. In this regard, the way they are visualized is vital to their success.The familiarity of blue underlined hyperlinks goes a long way to explaining its longevity as design element, despite being a relic from a simpler time. Nielsen, whose views on link visualization have evolved over the years, notes that �consistency is the key to teaching users what link colours mean,�. Blue has historically provided that consistency, cementing the psychological association of blue with clickability.