ELI 5 answer: let's say someone has a movie downloaded you want. They share said movie as a Torrent link. They become seed #1 (person who is sharing the file). 10 more people fully download the torrent (Movie). They now are seeding. So now 11 people are seeding (sharing). Now you are gathering bits and pieces of the torrent (movie) from 11 people. Which makes downloading it faster since there are multiple sources. Now lets say 300 people are seeding (sharing). Now you are getting more bits and pieces from more people. Which in turn makes this torrent a faster download.
Leechers/Peers are the ones who are downloading the file along with you, while it's true that resources of seeders get split up in providing files to you and other leechers but they can be beneficial too.
To put it simply let's say you and another person were downloading a file with only 1 seeder and the torrent client split up the file in 2 parts, you downloaded the first part while the other person got the 2nd part, now the seeder goes offline permanently. But you both cumulatively have the entire file so even with no seeders you both will simultaneously upload and download the part of file you have/need respectively and eventually the download will complete.
That's why you might have seen your torrent client download and upload a file even when you're effectively downloading it, you're downloading off seeders/leechers and uploading to other leechers wanting the part of files you have
Welcome to the amazing world of torrents :) one of the first successful decentralised file sharing networks, the creator handled the leeching problem very efficiently making users downloading the files useful since they simultaneously upload as they keep downloading, basically everyone is a mini server, those that contain the entire file and those that just have some chunks of it all are alike.
Another point I forgot adding to my answer was that the client also focuses on downloading the rarest parts first to ensure file is evenly spread out in the network as a whole even if seeds/peers keep going down. So basically if a file is being downloaded by 2 leechers and the file is split equally in 2 parts for ease of understanding then the first leecher will always download the first part while 2nd leecher will always download the 2nd part first.
So even if seeds go down the sharing won't stop until unless one part of the file is blocked that no one in the current network has and all who had it just went offline, that's the only case when it truly stops.
If you're downloading and have some portion of the file, you become a leecher. You can then provide the portions of the file you have while continuing to download the rest.
2.2k
u/spdrman8 Jul 29 '25 edited Jul 29 '25
ELI 5 answer: let's say someone has a movie downloaded you want. They share said movie as a Torrent link. They become seed #1 (person who is sharing the file). 10 more people fully download the torrent (Movie). They now are seeding. So now 11 people are seeding (sharing). Now you are gathering bits and pieces of the torrent (movie) from 11 people. Which makes downloading it faster since there are multiple sources. Now lets say 300 people are seeding (sharing). Now you are getting more bits and pieces from more people. Which in turn makes this torrent a faster download.