A silicone or polysiloxane are polymers made up of siloxane (−R2Si−O−SiR2−, where R = organic group). They are typically colorless, oils or rubber-like substances. Silicones are used in sealants, adhesives, lubricants, medicine, cooking utensils, and thermal and electrical insulation. Some common forms include silicone oil, silicone grease, silicone rubber, silicone resin, and silicone caulk.