Tor is a network of virtual tunnels that allows people and groups to improve their privacy and security on the Internet. It also enables software developers to create new communication tools with built-in privacy features. Tor provides the foundation for a range of applications that allow organizations and individuals to share information over public networks without compromising their privacy.
Tor can also be used when penetration testing. Tor can use multiple proxies to hide your source address. there are plugins for Firefox. This tool is as easy to use as clicking a button.