Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Though a submersible is a small vehicle designed to operate underwater, the term submersible is often used to differentiate from other underwater vehicles known as submarines, in that a submarine is a fully autonomous craft, capable of renewing its own power and breathing air, whereas a submersible is usually supported by a surface vessel, platform, shore team or sometimes a larger submarine. There are many types of submersibles, including both manned and unmanned craft employed in many roles such as oceanography, underwater archaeology, ocean exploration, adventure, equipment maintenance/recovery or underwater videography. Learn more about submersibles, their functions and abilities in the following pages.