Petroleum engineers study the earth to find oil and gas reservoirs. They design equipment and processes to extract oil and gas efficiently and profitably. There are three major types of petroleum engineering: drilling engineers oversee drilling operations and well safety; production engineers study well characteristics and control production; and reservoir engineers design field development and determine how to recover the most resources. A bachelor's degree in petroleum engineering is required, which includes courses in math, science, and engineering, with a focus on subjects related to drilling, production, and reservoirs in the last two years. The objective of petroleum engineering is to supervise and manage oil field operations.