Cursor on shopping cart icon button, studio shot © Ed Honowitz, Photodisc, Getty Images

Fraudsters are constantly looking to take advantage of online shoppers prone to making novice errors. Common mistakes that leave people vulnerable include shopping on websites that aren't secure, giving out too much personal information, and leaving computers open to viruses.

Here are 10 ways to stay safe while shopping online:

Stay away from fishy-looking sites. You can't always tell when a website isn't legitimate, but red flags include poor design, a strange or nonsensical Web address, and multiple pop-up windows you can't close. If you notice any of these suspicious signs, stop shopping and close your browser windows.

Avoid clicking on hyperlinks embedded in emails. The Better Business Bureau warns that legitimate businesses don't send emails asking for follow-up financial information. If an email, even one that claims to be from a familiar retailer, asks you to visit an outside site, don't do it -- it could be redirecting you to a scam site. Instead of clicking on a hyperlink, key the Web address that you want to visit into your browser manually.

Shop on secure websites only. Adam Levin, the founder of and Identity Theft 911, suggests looking for "https" instead of just "http" in the address bar. Also, he adds, be sure your computer's anti-virus software is up to date, since you may come across viruses when surfing online for deals and good buys.

Never, ever give your Social Security number to anyone online. If a site asks for it during the checkout process, it's probably a scam site, says Levin.

Take advantage of the automatic identity-theft protection that comes with many credit cards. That's one reason to use your credit card instead of debit cards or cash while shopping. If you see erroneous charges on your statement, you can call your credit card company, which should investigate on your behalf.

The Better Business Bureau points out that credit card companies are required to allow shoppers to dispute charges, and many companies cover charges made on stolen cards. Check your credit card statements frequently (don't wait until you get your monthly bill); many card companies have time limits for disputing charges.

Change up your passwords. With consumers asked to remember dozens of passwords for various retailers, banks and accounts, it's almost impossible to remember them all, especially since they often include mixes of numbers and letters. Either keep careful track in a secure document, rely on mnemonic devices to boost your memory, or come up with some other clever strategy -- but don't stick with simple passwords that are easy to guess.

Review your rights. The Better Business Bureau reminds shoppers that if products aren't shipping on time, consumers have the right to cancel the order and get a refund. They can also reject merchandise they deem defective or misrepresented.

Wield that cellphone carefully. Security firm BitDefender reports that shopping with mobile devices can come with its own set of security challenges, since shortened URLs can more easily trick shoppers into visiting harmful sites. Also, public Wi-Fi access is convenient, but it can leave your personal information accessible to hackers, so avoid entering passwords and credit card numbers while in public hotspots.

Avoid strangers on social media. Although many retailers use social media to drum up business, sometimes their accounts get hacked and you're sent a dangerous message or tweet designed to look legitimate. Fraudsters also send malicious messages through social networks. BitDefender recommends treating messages from strangers as spam -- just ignore them.

Don't click on fake e-cards. E-greetings are welcomed by most people, but the security firm AppRiver says fake cards can spread viruses. It recommends that consumers delete cards that come from unfamiliar addresses.

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