Like another poster stated, debit cards don't build credit, but there is one HUGE problem with debit cards.

If someone steals your card (or number) with a credit card and spends money with it, the credit card company is out the money.

If someone steals your card (or number) with a debit card and spends money with it, YOU are out the money until your bank is benevolent enough to return it.

I don't know about you, but I'd rather have someone steal Visa's money than my money.

Debit cards don't build your credit score. I learned this the hard way when I started my first job and couldn't get a reasonable credit card, despite 5 years of using a debit card (and a healthy salary)