The one piece of advice that may save you some headaches if you plan to shop online this holiday season: “Never trust, always verify,” according to Murat Kantarcioglu, professor of computer science at Virginia Tech.

Kantarcioglu said you’re going to be tempted this holiday season by online ads, but he said you have to remain vigilant.

“Don’t risk buying stuff from a website that you’ve never heard of before,” he told WTOP.

His advice is to go directly to the websites where you want to shop and check the deals.

You’re also going to get a lot off deal offers in your email, but Kantarcioglu said the same advice applies.

“Example, you get an email claiming there’s a super deal on some product you are looking for on Amazon; go to Amazon, search for the product and see if it’s really there,” he said.

There are also scammers who try to get you after an online transaction, Kantarcioglu said.

“’Your shipping got delayed on the product you bought, or there’s a package coming to you. Click here to see the new delivery date,’” he said when explaining what one of those scams might look like.

Instead of clicking, go back to the website where the purchase was made and track the shipping there.

When it comes to how you pay online, Kantarcioglu said it’s always better to use a credit card instead of a debit card. Credit cards offer better fraud protection, he said, and are much safer to use online. He added there’s extra protection with some credit cards that offer the ability to generate a virtual card number.

Kantarcioglu said not all credit card companies support this service, so you need to check with your card company.

Because scammers are getting increasingly sophisticated, Kantarcioglu said customers must be smarter with online purchases.

“They are using AI and other tools to make less mistakes than in the past,” he said.