Using the Web can seriously dangerous in some places. People who post criticism of authorities could be jailed, flogged, or even killed if they’re caught. The Tor Project tries to protect these people by giving them hard-to-trace Web access.
Homeland Security doesn’t like it when Americans can communicate without being spied on. In 2015, the Kilton Library in Lebanon, NH, set up a Tor node. DHS paid them a “visit” to let them know they didn’t like it. The node was suspended for a while, but DHS in fact had no legal authority to tell them to stop. Backed by strong community support, the node came back and is still running. The Library Freedom Project promotes the use of Tor nodes and other anti-surveillance technologies in libraries.
It’s easy to use Tor. Just download the browser and start using it. It’s a Firefox browser modified to connect to the Tor network and minimize the ways someone can identify you. It will connect through a series of anonymizing nodes, and no one at the other end will be able to tell by cues like IP address where the connection came from. Using it intelligently takes some understanding, though.
The first time you use the browser, you should click on the onion in the toolbar and bring up “Privacy and security settings.” You can select from the default (lowest) level, which is still pretty good, to several higher levels, or you can customize the features you enable.
(Removed a paragraph here that didn’t get the privacy situation with the ISP right. Sorry.)
If you drop clues about your identity, you lose a lot of your protection. Don’t log into any accounts that can be tied back to you. When you’re searching, it’s best not to “Google” but to use a site that respects your privacy more, such as Startpage or DuckDuckGo. Google’s big enough that it doesn’t need your free advertising.
Browsing may be slow, because of the circuitous path your requests take. Your exit node will often be in another country, so localization may do weird things to you, such as coming up in a foreign language.
Tor isn’t censorship-proof. In some cases, you’ll run into more censorship with Tor than without it. Exit nodes, the ones that connect out from the Tor network to the destination, may block requests. If the exit node is in another country, it may get around local censorship or be locally censored. The service provider you connect through might block some domains.
There are various tricks for narrowing down the kind of computer, operating system, and browser you’re using. Tor tries to defeat as many of these as possible, but it can’t stop them all. Your best bet, if privacy is a vital concern, may be to use a very popular brand of laptop running Windows 10. Yes, even if you hate Windows.
Adding Firefox extensions is technically possible, but it could compromise your security. In most cases you just shouldn’t.
This is just an introduction to using Tor. Here are some more sources of information and advice: