BitTorrent is one of the most widely used technologies on the internet, and also one of the most misunderstood. It is often treated as another word for piracy, yet it is simply a way of sharing files. This explainer covers how it works, what it is legitimately used for, and the common myths that lead people into trouble.
It is part of the background reading for Rarbgget.org, our independent guide to the RARBG name. It does not link to any torrent site or explain how to obtain copyrighted material.
The Problem BitTorrent Solves
Normally, when you download a file, it comes from one server. If thousands of people want the same large file at once, that server needs a lot of bandwidth, which is expensive. BitTorrent, designed by programmer Bram Cohen and released in 2001, takes a different approach: everyone downloading a file also uploads the pieces they already have to others.
How It Works, Step by Step
- The file is split into pieces. A large file is divided into many small pieces, and each piece is given a unique fingerprint called a hash.
- A small description is created. A .torrent file, or a “magnet link”, contains the file names, the piece hashes and information about how to find other people sharing it. It does not contain the file itself.
- Peers find each other. Your BitTorrent program uses trackers or a distributed system called DHT to find other computers, known as peers, that have the file.
- Pieces are swapped. Your program downloads different pieces from different peers at the same time and uploads the pieces it already has.
- Every piece is verified. Each piece is checked against its hash, so a corrupted piece is discarded and fetched again.
- Seeding. Once you have the whole file, you can keep sharing it. People with the complete file are called seeders; the whole group is called a swarm.
Legitimate Uses of BitTorrent
BitTorrent is legal technology with many lawful uses:
- Many Linux distributions offer official torrent downloads of their installation images on their own websites, which spreads the load across users.
- The Internet Archive provides torrents for many items in its collection, including public-domain films and texts.
- Game companies and software publishers have used peer-to-peer technology to distribute large updates.
- Researchers and organisations use it to share large open datasets.
What makes torrenting illegal in many countries is not the technology but the content: sharing copyrighted films, series, games, music or software without permission.
The Privacy Trade-Off
Because peers connect directly to one another, every member of a swarm can see the IP addresses of the others. This is a built-in part of how the protocol works. Copyright enforcement companies join swarms for popular copyrighted files, record the IP addresses they see, and send notices through internet providers. A VPN changes which address is visible, as explained in our VPN basics guide, but it does not change the legal position.
Torrent Myths and Facts
| Myth | Fact |
|---|---|
| Torrenting is always illegal. | The technology is legal. Sharing copyrighted content without permission is what breaks the law in many countries. |
| If I only download and never upload, I am fine. | Most BitTorrent programs upload pieces while downloading, and in many countries downloading copyrighted material without permission is unlawful anyway. |
| Incognito mode hides my torrenting. | Private browsing only stops your browser saving history. It does nothing to hide your IP address from peers. |
| A VPN makes it legal. | A VPN hides your IP address; it does not change copyright law. |
| Popular torrents are safe. | Popularity is easy to fake, and malware is regularly disguised as popular releases. |
| A site with a famous name is the original. | Names and layouts are easy to copy. The original RARBG closed in 2023; see what happened to RARBG. |
Where Torrent Indexes Fit In
A torrent index is a website that lists .torrent files and magnet links, usually with descriptions and comments. It does not need to host the files themselves. RARBG was one of the best-known indexes before it closed. Since then, copycat indexes using its name have appeared, often with aggressive advertising and fake download buttons. Our guide to spotting fake torrent mirror sites explains how to recognise them.
Staying Safe
- Only download torrents from official sources, such as a software project’s own website.
- Check that the files you receive match what you expected, and never run an executable that claims to be a video.
- Keep your BitTorrent program up to date and download it only from its official website.
- For films and series, use licensed or public-domain services instead.
For our overview of the RARBG name and the domains that borrow it, visit Rarbgget.org.
Key Terms at a Glance
- Peer: any computer taking part in sharing a file.
- Seeder: a peer that has the complete file and is uploading it.
- Leecher: a peer that is still downloading.
- Swarm: all the peers sharing one torrent.
- Tracker: a server that helps peers find each other.
- DHT: a distributed system that lets peers find each other without a tracker.
- Magnet link: a short link containing a torrent’s unique identifier instead of a separate .torrent file.
- Hash: a digital fingerprint used to check that each piece is correct.
Understanding these terms makes it much easier to see why a torrent index is not a file host, and why privacy on BitTorrent works differently from ordinary web browsing.
None of this makes BitTorrent good or bad in itself. Like email or cloud storage, it is a tool, and whether its use is lawful depends on what is being shared and whether the people sharing it have permission to do so.
Frequently Asked Questions
Is BitTorrent legal?
Yes, the technology is legal and widely used for lawful purposes. Sharing copyrighted material without permission is what is illegal in many countries.
Does a torrent file contain the movie?
No. A .torrent file or magnet link only describes the content and helps your program find peers who have it.
Can other people see my IP address when I torrent?
Yes. Everyone in the same swarm can see the IP addresses of the peers they connect to.
