VPN stands for Virtual Private Network, and using one allows you to anonymize your internet activity via some level of encryption. Encryption is a way of masking the contents of what you do online so only authorized parties can understand it.
VPNs sound like “they’d be technically challenging to implement, but it’s actually made to be very user friendly,” according to Heid. Here’s the gist: If you use a VPN, your internet provider won’t be able to see your traffic. A VPN lets you “purchase a proxy server,” allowing you to browse the internet from a different machine, perhaps miles away from your actual location. Most, if not all VPNs will incur a small subscription fee, which is often paid on a monthly or annual basis. VPNs shut ISPs in the dark. While using one, ISPs "don’t know what you’re doing, other than that you’re connecting to a VPN service,” says Heid. Using any number of easy to implement VPNs, like HotSpot Shield, DotVPN, or TunelloVPN, among others, make your internet activity look like gibberish to advertisers. Make sure the VPN service you subscribe to has satisfactory ratings, of course, because you're most likely going to be paying for one. (There are some free VPN programs, such as OpenVPN, which is pretty well-regarded).