As retailers slash prices left and right, online shoppers have to be on the lookout for good deals and beware of deals that are too good to be true.

Online shoppers prowling the Web for deals have to be extra careful on Cyber Monday, since scammers will take advantage of users who may not realize that the Web sites they visit may not be legitimate. Since advertisements promising deep discounts are the norm rather than the exception on the year’s biggest online shopping day, shoppers may be tempted to let their guard down and click pop-ups or banner ads promising unbelievable deals.

The Better Business Bureau has put up some tips for the holiday season, including a recommendation that online shoppers use their credit cards for purchases. In case of fraud, it’s a bit easier to dispute and control credit card charges. It’s a little more difficult with debit card charges, which give thieves direct access to your checking or savings accounts.

Good rules of the road also include checking that a site has an “https://” heading before entering your payment or personal information. That extra “s” in the start of a URL and/or a lock icon in your browser window is a signal that the site is secure.

You should also never respond to e-mails that ask for your personal or financial information, even if the message claims that the information is needed to resolve an order. Legitimate sites shouldn’t even ask you to e-mail that kind of information to them. If you receive that kind of e-mail and are concerned about an order’s status, then you should look up the company’s customer service department’s phone number or e-mail on its Web site and contact it with your concerns.

As LifeLock chairman and CEO Todd Davis told The Washington Post, e-mails or ads advertising false charities are particularly prevalent at this time of year, as scammers look to take advantage of the giving spirit of the season. Check with the Better Business Bureau or the nonprofit search site Guidestar if you have doubts about the legitimacy of a charity you want to support.

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