Why Does LimeWire Get Launched?

[Cuco]

I use a Mac; run Transmission 1.54. While using "Some Tracker," whenever I try to download a video and double click on the "Magnet" icon "LimeWire" gets launched, and whenever I double click on the "Green" icon I get the following alert from my browser, "Safari can't connect to the server."

Why does LimeWire get launched? And isn't LimeWire a very slow way of downloading?

[Jordan]

+1 to x190's answer

[tireboy]

thanks for the infooo!