Tor is probably the best-known privacy network and also one of the best at protecting your personal data. It is free software for enabling anonymous communication.
According to Wikipedia:
The name is derived from an acronym for the original software project name “The Onion Router”. Tor directs Internet traffic through a free, worldwide, volunteer overlay network consisting of more than seven thousand relays to conceal a user’s location and usage from anyone conducting network surveillance or traffic analysis. Using Tor makes it more difficult to trace Internet activity to the user: this includes “visits to Web sites, online posts, instant messages, and other communication forms”. Tor’s intended use is to protect the personal privacy of its users, as well as their freedom and ability to conduct confidential communication by keeping their Internet activities from being monitored.
To use the full capabilities of accessing web pages on the Tor network, the Tor Browser is required. It is also free software and is available for Windows, Macintosh, Linux, Open BSD UNIX, and also for Android systems. Now The Tor Project has released Tor Browser 8.0 with huge changes.
You can learn more and also to download the Tor Browser from The Tor Project web site, go to: https://www.torproject.org.