μTorrent, often stylized as uTorrent and read as either "You Torrent," "Myu Torrent," or "Micro Torrent," is a free torrent client for Windows originally developed by Ludvig Strigeus in C++. The program was later sold to BitTorrent, Inc. The program began as a free light-weight torrent client, but the developer wanted to monetize it, so a lot of obnoxious and potentially harmful adware was added and features were eliminated and moved to the pay-version.
I still use an old version of μTorrent as my primary torrent client. I prefer its lightweight footprint and simple interface over any of the more CPU-intensive feature-rich clients.
This is the last decent version before the developer started bundling in so much adware and eliminating free features that it became garbage.