A debit card, or check card, is issued by your bank, commonly has the Visa or Mastercard logo, and draws directly from your checking account.  This can be the same card for ATM access to your account.  Debit cards allow you to shop and pay online or by phone without running up debt.  They do not help build credit but can be an alternative for someone whose credit history makes it difficult to obtain a credit card. It is a faster way to pay than using a paper check and it's safer than carrying around a lot of cash.  It can save time to "pay at the pump," rather than running in to prepay and guessing how much gas you'll need.

A debit card offers the convenience of a credit card but you must be aware of the possible pitfalls.  You can use it nearly anywhere a credit card is accepted, though there may be certain exceptions (some car rentals, for example).  You must be sure to keep all your receipts and balance your checking account often.  This can be a challenge if you make many purchases in a short amount of time.  Losing just one receipt after a day of shopping can cause you to overdraw your account and rack up fees with your bank.  If your card is lost or stolen, or if someone gets your card number, a thief may have direct access to all the money in your bank account until you discover this.  Even once it's reported your money may be tied up until the issue is resolved.  Be sure to check your bank statement often and report any unauthorized charges. 

Sometimes retailers will ask you "credit or debit?" when you pay with your debit card.  Even though the money is still being taken out of your checking account, it can be processed as a credit transaction.  This is considered to be an offline transaction, you will not be required to punch your PIN into the card reader and you just sign for the charge.  Your account balance may not immediately reflect those purchases since these take a little longer to process.  If used as debit, it is an online tranaction and you will be required to use your PIN.  Be sure to carefully guard your PIN as it allows direct access at any ATM!  You can often get cash back with your purchase and you may be charged ATM fees.  Check with your bank to be aware of any possible charges so you don't get any surprises on your next statement.

Banks may have standard limits on debit card purchases, maybe a daily limit or a per purchase limit, or both.  I remember when I tried to buy some furniture with my debit card and it was denied even though I knew I had the money in my account.   To save time and embarrassment, you can request to have these limits raised before you make major purchases.  But don't forget these limits are there to protect you against theft or fraud, so it might be safer to temporarily raise the limits when you are planning large purchases and then lower them back to what you would normally need them to be.

A debit card can make shopping and paying bills easier and faster.  Just don't forget there are added risks with a debit card.  Retailers don't usually ask for ID when you make purchases and unfortunately a lot of them don't even check your signature on the back of the card.   Safeguard this card, all your receipts, the card number, and your PIN like it's all the money you have in your bank account.