Whats the difference between a boat and a ship?

Their size is the differance. A boat is something you could pull on a trailer with your truck. A ship is far to large to be driving down the road with. Why are you so terrified of pictures?

The difference is the weight of the vessel. Anything over 200 tons is considered to be a ship.

Ships are very large boats!

Ships always have displacement hulls and move through the water at speeds that are a function of the square root of their waterline length times a contstant, usually about 1.3. They are designed to carry a significant load as a percentage of their total weight (or displacement). The load can be anything including extra structure to accomodate passengers. There are large vessels that are boats because they lack displacement hulls and/or lack cargo capacity, and small vessels that could be considered ships due to their hull design and cargo carrying capacity. Both have to have a means of self propulsion, otherwise it's a barge. Ships are also designed to be seaworthy for most sea conditions and can stay out on open water for extended periods. Boats are more limited in both regards. Example: A tug of any size is a boat because it is designed to be a waterborn "tractor" rather than a cargo carrying vessel. A 35 foot sailboat designed for offshore work and ocean passages that can also be safely loaded to 40% of it's empty weight is a tiny ship. A giant hydropane ferry is a boat because it's unsafe in rough sea conditions and can't carry enough fuel to make extended ocean passages and still have decent cargo capacity.

a ship is supposed to be sea worhy (i think) and has the ability to cross an ocean safely, this is why most shipps are bigger than boats.

The Internation Rules for Prevention of Collision at Sea defines a ship as being 'any vessel that is not propelled by oars'. Thus, if the vessel is rowed or sculled, it must be a boat.

a book called dictionary will give you the answers and more.

There is no strict nor universally agreed distinction. Only tradition. Yes submarines are called boats in the Navy but not by any dictionary definition. Generally to command a ship you need strict Government regulated license although is some countries, not the UK, you need a license even to command a boat. The "little ships" of Dunkirk fame were boats but they performed a function more associated with ships. Many people would regard a vessel over 125 feet long to be a ship.

ok a boat is a little thing compared to a ship. a ship would be something like the Titanic, Brittanic, Olympic, or the Lusitania!! hope this helps!!