ROVs, or remotely operated vehicles, are robots that go where humans can't. Space probes may be regarded as remotely operated vehicles, though the term usually refers to the ocean-based tethered versions - remotely operated underwater vehicles. These are used for all sorts of useful purposes, like prospecting for submarine oil deposits or observing the underbelly of Antarctic pack ice. ROVs are important to humanity's future, as they will be used to locate resource deposits deep underwater to meet our future needs. For instance, the ocean floor contains huge amounts of methane clathrate, a clean-burning fuel, and numerous manganese nodules, which can be used to make important alloys.
ROVs were initially developed from funding by the US Navy in the 1960s. The initial interest was to recover sunken ships and other lost artifacts from the ocean floor. The world record for a scuba diver descent is only 318m (1,043ft), but state-of-the-art ROVs can dive as deep as 3,000m (9,842ft). This only goes down to about the depth of half the world's oceans - but further improvements will open up the remainder. ROVs can explore environments too hostile for human divers, such as deep-sea geothermal vents and polar waters. Science missions making use of ROVs have discovered a number of new species and ecosystems. The extremophilic bacteria and organisms they have discovered have been seen by some as signs that life could survive in exotic environments on other planets.
To keep in contact with the surface and receive power and instructions, ROVs are usually connected to a surface ship by an umbilical cable. This cable contains data links, power cords, and for high-power applications such as burrowing, hydraulics. ROVs were critical to the progress of oil and gas companies in the 1980s, who looked away from land deposits to see what the oceans had to offer. Since ROVs have been deployed, many billions of dollars worth of oil reserves have been discovered at the bottom of oceans worldwide. Anything that lives in the ocean eventually dies and sinks to the bottom, leaving a deep layer of organic muck that gets turned into useful hydrocarbons after millions of years.
ROVs can also be used to lay undersea cables, which are critical for our worldwide communications infrastructure. These cables must often be buried under a few feet of earth to ensure their stability.
