Submersibles are small underwater vehicles or watercraft designed for exploration of the underwater world. Unlike submarines that can operate on its own, submersibles usually receive support from a more extensive water vehicle, shore team, or surface vehicles. Earlier submersibles were used as weapons of war to destroy enemy ships.

Nowadays, humans use them for offshore engineering, ocean exploration, tourism, adventure travel, recovery missions of property and lost equipment. Technology advancement has also made it possible for governments and institutions to build unmanned submersibles for performing specialized tasks. These high-tech submersibles have sensors, power sources, video cameras, scanning sonars, geophysical devices, and mechanical arms to perform a wide variety of tasks.