Have you ever had your day interrupted by a spam call offering you a free vacation, informing you that the IRS is suing you, or just containing plain gibberish? This has probably happened to you more than once — in a single day.

We have all had our day (or night, for that matter) interrupted by the unexpected, and ultimately unwanted, ringing of our phone — and it’s then a robot on the other end of the line. Nationwide, there were 26.3 billion of these calls last year, and the number continues to climb. The robots who want to repay our student debts or give us a free vacation are apparently very, very generous.

We might think of these calls as merely annoying, but robocallers will exploit your frustration, fear, or curiosity to take advantage of you. They use new advances in technology to steal your hard-earned money, and as scams become more complex, a simple misstep — even a single word — can cost you a lot. Here are three pesky scams to keep an eye out for.

One easy-to-fall for trick is the “Can you hear me?” scam. As soon as you pick up, a recording designed to get you to say “Yes” starts playing. This can include questions such as, “Can you hear me?” or “Is this Andrew?” The scammer then uses the recording of you saying “Yes” to authorize charges to your credit card. This is why you should hang up without saying anything if you pick up a robocall. Venting your frustration to the robocaller may only make the situation worse.

But even if you don’t answer a robocall and wait to call back, you could still find yourself in trouble. Take the “one ring” scam, for example. Scammers will call your phone but hang up after only one ring, hoping that you return the missed call. Sometimes they will make the call seem more urgent by calling multiple times, usually in the middle of the night. Once you call back, however, you have fallen into the trap; the number is an international toll line that will cause you to rack up huge fees on your next phone bill. If you get a single ring phone call, it is best not to return it, even if it came many times from the same number.

Finally, you should be on the lookout for robocalls that use prerecorded messages for more “traditional” scams. Many of these, such as fake calls from the IRS, prey on consumers’ fears and threaten fines or jail time for various infractions. In the IRS scam, a prerecorded message declares that your taxes are late, and that penalty fees are due immediately. Other scams involve robocalls claiming to be from Google asking for money in exchange for ranking you highly in Google search results, from the Chinese consulate requesting a bank transfer for a package they are holding for you, or from companies selling health insurance. In general, you should be wary of calls asking for money over the phone.

As with many technologies, robocalls can be both useful — such as for emergency notifications or school closing notifications — and harmful. However, as consumers, we should never have to face the dilemma of picking up a call and exposing ourselves to a scam, or letting the phone ring and missing a potentially important call.

Though there are some protections for consumers, including the Do Not Call list or reporting unwanted calls to the FTC, we are still burdened by incessant and dangerous spam calls. There is a long way to go to resolving this top consumer complaint. Until then, we have to remain cautious to avoid falling into robocall traps.

Andrew Noh is a consumer watchdog intern for Penn PIRG, the Pennsylvania arm of the federation of state Public Interest Research Groups.