Metal halides are chemical compounds formed by the combination of metal elements with halogens, which are a group of elements that include fluorine, chlorine, bromine, and iodine. These compounds can be ionic or covalent, depending on the nature of the metal and halogen involved. Common examples include sodium chloride (table salt) and copper(II) bromide. Metal halides are often used in various applications, such as in the production of semiconductors, in lighting (like halogen lamps), and in chemical synthesis. Their properties, such as solubility and melting points, vary widely based on the specific metal and halogen combination.