Oil-based fluids are liquids that primarily consist of oils, often derived from petroleum. These fluids are commonly used in various industries, including drilling and lubrication, due to their ability to reduce friction and provide cooling. They can also be formulated with additives to enhance their performance and stability. In the context of drilling, oil-based fluids are used as drilling muds to help remove cuttings from the wellbore and maintain pressure. Their properties allow for better control in challenging geological formations, making them essential for efficient and safe drilling operations.