Traveling upstream on the Menam (Chao Phraya) River past Bangkok reveals many "longtails" floating on Thailand's giant river. Longtails, of course, are small boats equipped with general purpose engines instead of outboard marine engines. This type of engine has a long propeller shaft that sticks out of the boat, resembling a dragonfly's tail. The boat is called a "longtail" because of this propeller shaft. Longtails are indispensable to the lives of people in Thailand, as well as to those in other developing nations in Southeast Asia. They are an important means of livelihood, facilitating transportation and fishing.