Whether you’re sitting in an airport or doing classwork in a library, chances are you’ll need to use public Wi-Fi at some point in your life. But these networks, when unprotected, can be used by hackers as a channel to take advantage of the people using them. Some hotspots are specifically set up for this purpose—and they can be hard to tell apart from legitimate public networks. When you find yourself in a situation where public Wi-Fi is your only option, keep the following information—assembled by Mental Floss and Discover—in mind: It could keep you from falling victim to a fraudulent network.

1. The Wi-Fi network has a vague name.

If you have to use a public Wi-Fi network, it’s best to have an idea of where your free internet is coming from. Wi-Fi networks that are named after nearby businesses—like the coffee shop where you’re working or the department store across the street—are slightly more trustworthy than networks from mysterious sources. Networks with vague, too-good-to-be-true names, like “Free Airport Wi-Fi,” could be set up by people trying to hack your computer.

2. You haven’t confirmed the network name with someone trustworthy.

Even if a Wi-Fi network name sounds legitimate, you should always confirm it with a real person when you can. Upon checking into a hotel, or ordering something at a cafe, ask the person behind the counter for the Wi-Fi information. Make sure they’re as specific as possible so you know exactly what to look for when it’s time to go online. You can also use a semi-open network, which requires a few steps beyond just opening the internet on your phone. Businesses with this type of network typically require customers to purchase an item or ask an employee in order to get the password. This means that the pool of people sharing the network with you is limited, and the chances that someone will use the open network to hack your personal information are reduced.

3. The network name looks almost identical to another one in the area.

Not all hackers stop at putting “free” in their Wi-Fi network name and hoping someone will bite. Some of them make fraudulent networks called “evil twins” that look almost identical to real networks in the area. The differences are subtle, such as an extra character or a word that’s been capitalized (CoffeeShop_Wi-Fi instead of CoffeeshopWi-Fi, for example). When confirming a Wi-Fi network with a real person, write it down and double-check it against the name that pops up on your device. That way you can be sure you’re connecting to the real thing.

4. There wasn’t an opt-in page when you logged on.

You know the page that asks you to opt-in when connecting to a public Wi-Fi network? It’s a sign that the network you’re logging in to comes from a professional source. If a network lets you connect without asking you to agree to its terms of service, you should be wary of it.

5. The network required you to install something before you could use it.

Networks with opt-in pages shouldn’t be blindly trusted. When a network asks you to agree to something, don’t just click whichever option gets you to the internet fastest. If you don’t have time to analyze it thoroughly, at least scan the terms and conditions for any concerning words that jump out at you. (If you don’t understand what the terms mean, do a quick internet search to shed light on the situation.) You may be giving the network permission to collect and use your data for nefarious purposes without even realizing it. Any network that requires you to install software before using it should also be avoided.

6. The network isn’t on a reliable database of vetted networks.

Instead of trying your luck with the list of Wi-Fi networks your computer gives you, find a vetted list you can trust. Some apps collect airport Wi-Fi information from around the world and keep the network names and passwords in a searchable database. The benefit of these lists is that every name you see has been verified, so you can feel better about connecting to an unfamiliar network when you’re away from home.

If you’re worried your information may have been compromised, Discover can help. They monitor thousands of sites on the Dark Web and will alert you if they find your Social Security number. And it’s free for cardmembers who sign up. Learn more at Discover.