I welcome these questions. When clients are more informed about their treatment, they tend to feel more comfortable in our sessions and do better when they get home. And I don't believe clients who ask these questions are dummies, just so you know (I can't speak for the authors of the book). I expect that most people have little idea what CBT is and I'm happy to explain.
CBT refers to two different components: Cognitive is the thinking part of therapy; Behavioral is the doing.
The example I give most often: You're depressed because you've gained a lot of weight. You feel hopeless about ever losing the extra pounds. Your depression leaves you feeling unmotivated to exercise more.
"All I can think about is food."
"I deserve to eat this dessert."