: Each piece has a unique cryptographic hash (SHA-1) stored inside the .torrent file. Your torrent client uses these hashes to verify that each piece you download is not corrupted or tampered with.
In the context of a file, a "piece" is a small, equal-sized segment of the larger target file (or set of files) being shared. Torchlight III.torrent
For a file like Torchlight III.torrent , which manages a game download approximately in size: : Each piece has a unique cryptographic hash
: The BitTorrent protocol splits the game data into thousands of these pieces to allow decentralized downloading from multiple "peers" simultaneously. For a file like Torchlight III
A piece for this specific game might range from depending on how the creator of the torrent configured the "piece length". Torchlight III Depots - SteamDB
: If your download is stuck at 99%, it usually means the specific "piece" required to complete the file is not currently available from any seeders or peers in the swarm.