TOR is a network of private and other servers through which users connect to the internet in total anonymity. It is not about privacy and technically, unless you also encrypt communications themselves, your communications can be read on the other end, they just would not know who you are or who you sent the message to unless that information is contained in the actual message. Likewise, someone could see what web site you visited but not have a clue who or where you are. You information IS encrypted on your end and through the TOR network until it reaches an exit point bound for the internet, so your ISP etc. cannot log what you are doing at all.
There are separate tools to encrypt your traffic.
TOR is free and available for Windows, Linux, Mac and Android smart phones.
TOR originally stood for "The Onion Router" because of its many layers of security. It was created for DARPA by the US Navy and released into the public domain. The intention of TOR was to create a safe method for dissidents and others including government agencies to communicate in the most secure environment possible. The irony is that while our own military uses TOR ( along with millions of average humans ) our NSA, CIA, FBI and other spy agencies are frustrated because they have no way to infiltrate and read TOR communications. Naval Research created a system our own spy network cannot crack !
By way of TOR you can access thousands ( millions? ) of .onion domains which exist only via TOR networks. This is often referred to as the Deep or Dark Internet. It contains things you just cannot find via any Google search including a lot of illegal products and services world wide.
Once inside the "World of TOR" you can create totally anonymous email accounts, purchase (BitCoin) hosting and communicate with others with total anonymity as long as you don't provide your personal information to others once logged in.
TOR is indeed the wild west of the internet with all the good guys mingling with the worst. It is a necessary network often used by political dissidents to communicate without their own governments tracking them down. News organizations can gather information and speak with anonymous sources, protecting both the investigator and the informant.
Large companies may be using TOR to communicate via private encrypted email about secret product development and marketing etc. to avoid industrial espionage.
In an age where the "normal" internet is totally monitorable and not at all secure or private, TOR provides a very necessary method for communications where exposure for some could mean torture and death at the hands of repressive governments.
If you plan to use TOR please read up on how to properly set this up.
TOR is often slow and not really designed for the transfer of large files. Sites on the .onion network can be even slower and sometimes unreliable depending on the persons who manage them and the server locations.
PLEASE do not use TOR for illegal purposes, that is not it's intent.
TOR is not a place for children to surf the net so don't even consider it.
One good use for TOR even if it is a pain for normal email communications, is that you can use TOR to send a private key to unlock your encrypted emails then use your normal OS and email client with encryption to send and receive messages in the open. This will NOT prevent intruders from knowing who you send messages to but will make reading them impossible. If you do not need to hide whom you communicate with but must conceal what you say, this can make things easier. This is good for corporate emails where no one cares if you email "so-and -so" in product development but you don't want to expose company secrets.
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