Tor

Tor is a free overlay network for enabling anonymous communication. It is built on free and open-source software run by over seven thousand volunteer-operated relays worldwide, as well as by millions of users who route their internet traffic via random paths through these relays. This technique is called onion routing.
Using Tor makes it more difficult to trace a user's internet activity by preventing any single point on the internet (other than the user's device) from being able to view both where traffic originated from and where it is ultimately going to at the same time.