Armstrong World Industries, Inc is a corporation of Pennsylvania. They are famous as international manufacturer and designer of ceilings and floors. The corporation saw the light of business world through a joint effort of Thomas M. Armstrong and John D. Glass. The company was incorporated in 1891. Based in the region of Pennsylvania, they operate more than thirty-two plants around eight countries. In 1998, they acquired a leading hardwood cabinet manufacturer, Triangle Pacific Corp. Approximately eight thousand and five hundred employees are recruited in the branches that had $239.2 million as operating income in 2011; whereas, net sales rose to around $2.86 million.