It is well known that Internet is full of tracking software, advertising, and guys who are monitoring and collecting other people's data for various purposes. In other words, as long as it's on the Internet, you can be exposed to risk at any time. In addition, some websites may block or restrict your access depending on the IP address of your location (you must have encountered such situation: a website just shows you with 403 error). In these cases, using a VPN is the best solution at the moment.

For home users, accessing any website has to pass through a local ISP's default DNS servers, which decide whether we can access some websites or not, as well as their access speed and security. Althrough we can change the DNS, problem is, the method used to manually modify is too complicated and troublesome for ordinary users, so we'd better use tools instead.