With drilling at sea, the sea floor can sometimes be thousands of feet below sea level. Therefore, while with onshore drilling the ground provides a platform to drill, at sea an artificial drilling platform must be constructed. Off-shore drilling has resulted in the discovery and delivery of a great number of large natural gas deposits. Semi submersible rigs are the most common type of offshore drilling rigs, combining the advantages of submersible rigs with the ability to drill in deep water. Semi-submersible platforms provide an inherently more stable drilling platform than a drilling ship, making them better suited for the harshest conditions. They are less susceptible to wind and waves. In the oil well drilling business, having the latest equipment helps; but it’s the human element that still makes the difference.