How To Fix Input Signal Out Of Range Change Settings To 1600x900-60hz

Recently (about 2 weeks ago) I noticed sometimes my bandwidth is being eaten by BITS (Background Intelligent Transfer Service). I google'd about it and noticed people have guides on how to turn it off. Thing is, I don't want to turn it off without knowing what does it do because it may affect my system in some way. What does it exactly do? Is it the service responsible for the windows updates or something?