The act of boring a hole to determine whether hydrocarbons are present in commercially recoverable quantities in order to be able to produce these hydrocarbons. Drilling can be at first for exploratory purposes followed later by a development drilling. Drilling an oil/gas well is complex, expensive and potentially hazardous. The work is carried out by a drilling contractor under the supervision of the operating company. Wells are designed by a multi-disciplinary team comprised of drilling engineers, petroleum engineers, geologists and geophysicists in order to achieve the well’s objectives safely and at a reasonable cost