What's the difference between "credit" and "debit" when making a purchase with my card?

A Visa Debit Card is like having two cards in one. All purchases withdraw money from your checking account. Here's how each transaction works:
 

Use like a debit	Use like a credit
Press the "Debit" button on the retailer's terminal and then enter your four-digit Personal Identification Number (PIN)	Sign for your purchases by pressing the "Credit" button on the retailer's terminal
Limited to $500 withdrawal of your available balance or 25 transactions per day, whichever comes first	Funds are limited to your available balance
Transaction reflect on ATM balance immediately	Transaction typically does not reflect on ATM balance immediately. Could  be same day or up to five business days, depending on the merchant

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