Seeding in uTorrent refers to leaving a peers BitTorrent client open and available for additional individuals to download from. After a torrent job finishes downloading, if you leave the torrent job seeding, it uploads the file(s) to other peers so they can enjoy them too. Seeding is the lifeblood of BitTorrent sharing, and the entire system breaks down if no one is willing or able to seed a file. When a downloader starts uploading content, the peer becomes a seed. The length of time that you should leave the file seeding is not defined, but it is recommended that you share until the amount of data you upload reaches at least the same as the amount of data that you have downloaded, also known as reaching a 1.0 ratio. If you leave the swarm before even getting close to that ratio, you are labeled as a leecher.