Refiners are facilities or companies that process raw materials, particularly crude oil, into usable products. They separate and convert these materials into various fuels, such as gasoline, diesel, and jet fuel, as well as other products like lubricants and petrochemicals. The refining process involves several steps, including distillation, cracking, and reforming. In addition to oil, refiners may also work with metals, such as gold and silver, to extract pure materials from ores. This process often involves smelting and electrolytic refining. Overall, refiners play a crucial role in transforming raw resources into essential products for everyday use.