Activated carbon, also known as activated charcoal, is a highly porous form of carbon that has undergone a process called activation to increase its surface area and adsorption capacity. Activation is usually achieved by heating carbon-rich materials, such as wood, coconut shells, peat, coal, or other organic sources, in the presence of an oxidizing agent, which removes impurities and opens up a network of tiny pores. The resulting activated carbon has a large surface area, typically in the range of 500 to 1500 square meters per gram. The high surface area allows activated carbon to effectively adsorb a wide range of organic and inorganic substances from gases, liquids, and solutions. The adsorption process is based on the physical attraction of molecules to the carbon surface, where they are held by weak forces, such as van der Waals interactions.