The practice of discovering, tapping and developing oil and gas resources from land under the sea or other bodies of water. Typically, drilling for oil is done off the coast, but offshore drilling has also been done in lakes and inland seas. Offshore drilling can be an environmental danger, as proven by oil spills and drilling sites near the Arctic or areas close to shore. Offshore oil and gas production is more challenging than land-based installations due to the remote and harsher environment.