Traditionally, the marine people used the location of the stars at night and the sun during the day time, to attain a proper idea of direction. The marine farers did not face any problem when there was a clear sky. But when there were clouds in the sky and the directional stars became invisible, they faced lots of trouble, finding the right direction. After the compass was evolved, it was considered to be more dependable, than the skies. But the compass had its limitations too. The marine farers only got the idea of direction from the compass and not the idea of location. There was a dire need for such a device which could easily provide an idea of direction as well as location. This long standing demand of the marine people was addressed by the scientific community. With the invention of the marine GPS, the marine community was provided with a product, which was equally capable of presenting the accurate geographical position as well as the directions to the nearest ports and harbors. The marine GPS is today an essential accompaniment of most of the boat owners. The modern marine GPS are available in a variety of sizes and endowed with various functions. Most of the high or moderately priced marine GPS are generally available in waterproof casings, so that the people in the boat need not worry about saving the machine from water, they can rather concentrate on the data provided by the machine. Some marine GPS devices are available in the form of laptops while others are available as display units, along with a few essential buttons. It solely depends upon the boat owner, regarding the type of marine GPS he wants to buy. His final decision will depend upon the features he is looking for and also the platform of his choice. The marine GPS provides general directional information. It also provides information on the routes the boat can take, to reach the nearest port. The system also provides information on the various nearest ports along with information on a better catch. Many high priced marine GPS can actually help locate the maximum catch area and can direct the boat towards that area. You may be one of those boat owners, who are yet to buy a marine GPS unit. In that case, it is better to go to a nearby marine GPS shop and acquire information regarding the prices and features of the various models. You will then be able to decide on your appropriate requirement.