While there’s a lot of software and hardware behind the scenes, the way a VPN works for the user is pretty simple:
When you go online your traffic is routed directly to a host, like the server hosting a website. When you use a VPN service you connect to the VPN servers first then to the website servers.
When your connected to the VPN servers your IP address is swaped out and the VPN provides its own IP address attached to your traffic. From this point, all traffic passing through the VPN server is encrypted.
This process converts all the data into a code that prevents unauthorized access. Even if someone intercepted your traffic, they wouldn’t be able to decipher the data.
Every time you type in a web address there’s a step that happens almost instantaneously. The DNS (domain name system) is like a directory, matching text-based website addresses with the IP address linked to a website’s server. If someone wanted to track your activity, they could monitor DNS requests and see what you have been up to online.
But a VPN fixes that. Most VPN services also include their own DNS resolution system so the DNS request (when you type in a website address) looks like it’s coming from the VPN service instead of you.
It isn’t only hackers that can steal your data. Corporations also take your data and sell it on to advertising companies so they can use your information without you even knowing.
Basically, everything you do online can be monitored by your ISP (Internet Service Provider) and the only way to stop this is to use a secure, encrypted connection through a VPN.