Links are wonderful conveniences, as we all know (from clicking on them compulsively day in and day out). But they’re also distractions. Sometimes, they’re big distractions – we click on a link, then another, then another, and pretty soon we’ve forgotten what we’d started out to do or to read. Other times, they’re tiny distractions, little textual gnats buzzing around your head. Even if you don’t click on a link, your eyes notice it, and your frontal cortex has to fire up a bunch of neurons to decide whether to click or not. You may not notice the little extra cognitive load placed on your brain, but it’s there and it matters. People who read hypertext comprehend and learn less, studies show, than those who read the same material in printed form. The more links in a piece of writing, the bigger the hit on comprehension.