It is important to always keep in mind that a Wi-Fi (or wireless) network uses radio to transmit and receive information. This means that unless your information sent over Wi-Fi is encrypted, it can be intercepted by other Wi-Fi receivers and read by strangers. Briefly, staying safe can mean curtailing or modifying your normal internet activity while on public Wi-Fi networks such as those found at restaurants, airports, hotels, and so on.
If you do need to use a public WI-FI network, there are a number of additional steps you can take to help keep yourself safe. Read more about How to Stay Safe When On a Public Wi-Fi Network