Boats are watercrafts, which come in various sizes and provide a means of transport on the water. Boats have been in use from early civilization. In the ancient times, hollowing the trunks of trees having lightwoods made boats. Boats were also made from banana tree trunks, as banana trunks are waterproof and light. In the ancient times, boats served as a means of short distance transport as well as an aid in fishing. Slowly, bigger boats were built, using wood and other metals, such as copper and iron, which were used to carry more loads, for internal trading. Boats were also used for transporting people from one bank of the river, to the other. Boats are classified in various ways. The easiest way of classifying boats in according to their propelling systems. According to the propelling systems, boats are classified into sailing boats and motor boats. Sailing boats are those, which are propelled by using the sails. Sails are made up of various fabrics, from plain cloth to the modern synthetic sails. The motor boats are propelled by motor propellers, which run on fuel like gasoline or other alternative fuels. In recent times, there has been some developmental work regarding solar powered boats. In the modern world, boats have a lot of usage. There are specialized boats for surveillance and rescue work in the high seas. These boats are generally used by the coast guards of various countries. There are pilot boats, whose primary function is to help a big ship enter safely into the harbor. These boats are used by the various port agencies all over the world. There are tugboats, which are also used by the various port agencies. These tugboats are used to tow or push other larger vessels, in or out of the docking area. There are boats that are used for sporting purposes only. Boats such as the canoes, rafts, catamarans, etc. are extensively used for sports, recreation and adventure purposes. There are luxury boats too, which are commonly known as yachts. The yachts are very expensive pieces of luxury boats, which may have as many facilities as the owner desires. Generally, a yacht may have Jacuzzis, bars, bedrooms, dining areas, recreational area and even a helipad. Lifeboats are a special type of boats, which are generally attached with the bigger passenger carrying ships. The function of the lifeboats is to save lives, in cases of emergency situations. If there is a possibility that the ship is about to sink, the passengers are loaded into these lifeboats.