Raytheon and Raymarine
A Raytheon fishfinder is designed to mark fish, structure, and the features of the bottom on a display that is placed strategically so that the boat operator can easily view it. As you will see, some of these fishfinders offer the convenience of combining other technologies in one unit, such as GPS, radar and chartplotting. That way you can view everything you need to see on one display
First off, to avoid a lot of confusion, let me inform you that a company called Raymarine acquired Raytheon's Recreational Marine Division some years ago after a management buy-out. Raytheon is better known for their role as a leading defense contractor (the fourth largest in fact) for the United States government. They are one of the world's leading producers of guided missiles. Their TOW missiles were affixed to our Bradley Fighting vehicles in Iraq, while their Javelin missiles were used by our dismounted infantry squads. They are both highly accurate and effective weapons.
Since slippery fish can be somewhat like missiles themselves, Raytheon began to target them by developing and manufacturing fishfinders. They also make sonar, radar, and chartplotter devices for use in marine recreation, most notable of the saltwater variety. Like the majority of advanced technology, it goes to the military first and then trickles down to the general public for recreational or practical uses. The advent of geocaching is another good example of that trend. Just three days after the U.S. government enabled the general public to use GPS technology, clever recreationalists invented the hobby of geocaching, which entails using GPS devices to find hidden caches with trinkets and prizes in them. For more about that, read What are the Oldest Geocaches in the U.S.?
So Raytheon expertise in electronics, radar, and sonar greatly benefits anglers and boaters alike. Their prowess in developing high frequency side scanning sonar systems do particularly well in detecting and displaying all the contours and structure of ocean bottoms. For more on that type of technology, read the informative Techniques of Side Scanning Sonar.