Marine engineering refers to the design of marine propulsion systems. Marine propulsion is a system which is used to move ships and boats. Usually big ships are operated by systems which have an engine, a propeller, impeller, etc. The first engines used were steam engines, but now two-stroke or four-strokes are used. Before use of steam engines, ships were propelled with the help of wind. Marine engineers in Hollis design and maintain the mechanical system of ships and they usually work with an architect who designs the structure of ships. A marine engineer, in Hollis, is responsible for designing the propulsion, and other equipment required for the ship to move. Most marine engineers, in Hollis, are hired by private industries that build ships or make applications, tools used in them. These engineers also provide guidance as consultants to the ship crew who are under training and assist them to select the correct tools and equipment required by the ships. The tools in the ships are installed by these engineers to avoid any kind of risk. Hence, individuals who are marine engineers need to be well-versed with their job responsibilities. The career growth of a marine engineer also depends on the growth of the shipping firm for which he works. Marine engineering is a good career option.