The new Limewire has a torrent client built into it. The difference is the way you download.
Limewire you connect, search, and download from someone. When you download a torrent, you need a client that can check for people who have the file and the program open and you download parts from each person. If no one is “seeding” the file, then you are gonna get none or shitty speeds. If its a popular file and people are seeding it, then you will get fast ones.