Public wifi is certainly handy, especially when one is traveling. But there are risks involved, and the following article describes more about this risk:
Now, I'm not suggesting one doesn't use public wifi -- I use it frequently. What I do recommend is that you use a VPN (Virtual Private Network) whenever you're on a public wifi network.
hich VPN should one use, you might ask? There are many reviews available of VPNs on the internet. Here's one to read, if you have an interest:
f you're on public wifi, and not using a VPN, the first article above clearly shows how easy it is for hackers to snoop on your computer activity. So, just be careful when using public wifi.