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VPN - Virtual Private Network. you can use this to pretend you're in a network that you aren't local to. Often used to connect to work or school.

Proxy - A different computer your computer sends/receives messages through. The other end of these messages often believe you're the proxy server, and never know who you are.

Torrent - Download parts of a file from different hosts, and merge them locally to get the original file. Filed are sliced into tiny portions which you then source from everyone seeding that torrent - it is peer-to-peer (e.g the files don't have to hit a server) so it can stay more anonymous.

Thanks!

VPN: imagine you've got basic a tin can phone that you can put anywhere on the planet. Data goes from your side out to the world on the other side, and as far as the internet is concerned, it doesn't worry about the string, it just thinks you're the can on the end (for the most part). Typically encrypted and stable.

Proxy: same can, except you've given the other end to a friend, and the friend is asking the internet things for you, and relaying them back. Not typically encrypted, meaning they're usually faster. Time servers are a good example for use case

Torrent: still working on it NGL. My understanding is files can be split into multiple locations, pointing at each other, and are more resilient to failures.

In a nutshell, when your computer sends a "message" over the internet, that message goes to a computer at your ISP. The message has a "header" that says, "I'm this address, I'm trying to send it to that address." The ISP computer tries to find that address or, if it can't, it tries to find one it knows that's a little closer, and the process repeats. Every computer that gets this message has a chance to read it, store it, etc.

Proxy: a tiny bit of security against snooping

A "proxy" is a machine you tell your computer to ALWAYS send the message to first. This changes the way the "header" works a little bit. You send to the proxy "I'm this address, I want to send to that address". But when the proxy get it, it changes it to "I'm <the proxy address>, I want to send to that address". The message goes to other computers, and when it comes back to the proxy, the proxy rejiggers the message so it goes to you. This adds a bit of privacy, as everything past the proxy only knows the proxy sent the message. Note that your ISP is still between you and the Proxy, so there are still some computers that get a chance to see the message and/or record it.

VPN: a lot of things, but also more security against snooping

A VPN can be a lot of things, but right now we're interested in how it's sort of like a proxy. Normally for computers to talk directly to each other they need to be (oversimplified) connected to the same network, and "same network" here is a very restrictive concept. A VPN is a way to break the rules and treat a lot of "not connected" computers as if they were on the same network.

But in the context I'm smelling, you're also interested in "VPN tunnels". Oversimplified, a VPN using this feature ALWAYS demands that the traffic between you and the VPN is encrypted. So while you're still using your ISP's computers to transfer data, now all the ISP sees is "Oh, this is an encrypted message to a VPN. Think of it kind of like if you don't want people to know who you send a message to, you put the "real" envelope inside another envelope and mail it to someone else you trust. So it's LIKE a proxy, only now it hides the part BEFORE the proxy from anyone who can intercept it there. (Whether it's encrypted AFTER the VPN is up to whoever you're connecting to.)

Torrents: a file sharing protocol that's a completely different topic

One problem with downloading big files from a server is those servers might be unreliable. If it goes down, the download stops, and generally it's not easy to find another server or convince that other server to resume where you left off. This is especially true when doing "peer to peer" downloads, where the "server" is other peoples' machines which can be frequently losing connections or slow.

Torrents split files into lots of small "chunks" and everybody who has a complete chunk might be a "server" when you are downloading. If 100 people have the "chunk" you need, you can get it from the fastest one and keep doing that over and over. If 50 people lose their connection, you might not even notice and at worst you only lose 50 "chunks" of progress. This tends to lead to faster, more reliable downloads as long as people don't intentionally cut off uploads.

Probably what you meant to ask:

Torrents are amoral. They can be used to distribute legitimate files AND they can be used to distribute files that could get you in trouble whether or not we agree they should get you in trouble.

If you use a proxy to download torrents, your ISP could still potentially know you're downloading a file and, if they do some digging, what files you're downloading from who. That is bad news if you're doing things that could get you in trouble, and in some cases the ISP is obligated to report you or else they will get in trouble.

If you use a VPN, the ISP only knows you're receiving a lot of data through a VPN. Maybe they're suspicious it's something that could get you in trouble, but it could ALSO be something legitimate and they have no way to tell. The VPN company could, perhaps, do some snooping. But it's very bad for their business to do that, so many VPNs base themselves in countries where they are not obligated to do this snooping and promise they'll never do it.

This tech is, again, amoral. You can use it to hurt people while remaining anonymous. That's why a lot of people want to make it illegal. But that line of thinking is flawed, because sometimes there are very good reasons to want to be anonymous even when you aren't hurting people. I highly doubt people who say "I have nothing to hide" would be excited about a law that requires they shout their name and address while using a public restroom. "That's not the same", they'd say, but I don't find they can usually provide a good explanation why it's different. Please don't do things that hurt people with this knowledge and make those people feel more right.

I appreciate the explanation, this was really helpful.

Das a lot of words. Ty for your words.

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