You can use debit cards just like credit cards. In fact, according to my mom who works at a bank and explained it to me last night, the banks benefit when you use it as credit, because the retailer has to pay a service charge to them.

But yeah, if it weren't for debit, I wouldn't have Starfox 64 on my Wii! (also a quick tip if you get tired of punching in your PIN at retailers, you can hit "cancel" after you swipe your card and it'll process it as credit and just deduct the funds like normal)

(though you may want to check with your bank to be sure since we do live in different countries and things might work differently)