ADT, or American District Telegraph, is a company that provides security and automation solutions for homes and businesses. Founded in 1874, it has grown to become one of the largest security service providers in the United States. ADT offers a range of services, including alarm monitoring, video surveillance, and smart home technology. The company focuses on protecting properties and ensuring peace of mind for its customers. ADT's systems can be customized to meet individual needs, and they often include features like mobile app control and 24/7 monitoring. This makes it easier for users to manage their security from anywhere.