One major technological change has been the developement of the screen graph. The screen graph allows the angler to know a lot more about the atmosphere. The screen graph maps out the bottom of the lake to let an angler know the surface below him of her. The graph also shows anglers the depths of the body of water and the depths at which the fish are located, also know as Vexilar. Today fish finders are able to do amazing things.
Fish finders show the bottom surface of a lake.
This helps anglers in a big way. On the other hand someone fishing for bass would want to find a shallower bottom surface covered with folage such as weeds and tree branches. I think we can all see where fish finders can be helpful in this fashion. Fish finders also show the depth at which the fish are at. This allows anglers to decide what type of bait they would like to use.