How the seeders sistem function?

[Scott59]

Hi, on first, I'm sorry for my bad english but I'm italian and I wanna know something about utorrent and I found this forum.

Well, I want to know how the seeder sistem function, I explain: After you finish downloading a torrent, shows the writing "seeding", well, in this phase, I know I'm uploading the files for helping someone who want to downlad that torrent, but, in this phase, I noticed that the uploading speed is 0, or better, there isn't. So I ask: why? Probably that it was an error, but I wanna be sure.

Then, after finishing seeding a torrent, I'm a seeder, but when I delete that torrent from my pc, am I a seeder yet? Or, for being a seeder, I mustn't delete the torrent?

Thanks for the answer.