Thiols are organic compounds that contain a sulfur atom bonded to a carbon atom and a hydrogen atom, represented by the functional group -SH. They are similar to alcohols, which have an -OH group, but the presence of sulfur gives thiols distinct properties. Thiols are often characterized by their strong, sometimes unpleasant odors, reminiscent of rotten eggs or garlic. These compounds play important roles in various biological processes. For example, they are involved in the formation of disulfide bonds in proteins, which help maintain the structure and stability of enzymes and other biomolecules. Thiols are also used in industrial applications, such as in the production of rubber and as additives in petroleum products.