In your brain you call this association. I mention computers. That reminds of when your computer crashed. That, in turn, reminds you how long you were on hold when you called the computer company. And so on.
Hyperlinks work pretty much the same way.
You've seen hyperlinks if you've ever used a Windows help file. There are words that usually are in a different color than other's and underlined. When you move your cursor over those words, the cursor changes from an arrow to a hand with a pointing finger. The magic happens when you've got that pointing finger in place and you click your mouse. Those are the basic definitions.