Herding Dogs,German Shepards are one breed of Herd dog,says the encyclopedia.?

But I've never seen them, "work" as herd dogs.Can they be trained to herd sheep and cattle? I know they have good energy and stamnia,and they are rather gentle,despite the reputation for being guard and police dogs,so maybe they wouldn't attack sheepand I was trying to fins what their particular breed's purpose was.I know retrievers,retrieve birds for hunters,after the birds are shot.Chesapeake Bay retrievers can retrieve and swim in ice water due to think oily fur,and strong build,bred in them to hunt on that river.Beagles are bred to be rabbit hunting dogs,and foxhounds hunt foxes.So since German Shepards are herd dogs,exactly what do they herd and are any employed in herding currently that you know of?