F5 Networks, Inc. is a multinational American company which specializes in Application Delivery Networking (ADN) technology that optimizes the delivery of network-based applications and the security, performance, availability of servers, data storage devices, and other network resources. F5 is headquartered in Seattle, Washington and has development, manufacturing, and sales/marketing offices worldwide. F5 originally manufactured and sold some of the industry's first load balancing products. In 2010 and 2011, F5 Networks was on Fortune's list of 100 Fastest-Growing Companies worldwide. The company was also rated one of the top ten best-performing stocks by S&P 500 in 2010.