Asbestos is a naturally occurring fibrous mineral that was widely used in construction materials between the 1950s and 1980s. It's commonly found in a variety of building materials, including insulation, flooring, roofing, and cement. Although asbestos was used in a wide range of products due to its fire resistant and insulating properties, it has been linked to a number of serious health issues, including lung cancer, mesothelioma, and asbestosis.