Dell sells personal computers (PCs), servers, data storage devices, network switches, software, computer peripherals, HDTVs, cameras, printers, and electronics built by other manufacturers. The company is known for how it manages its supply chain and electronic commerce. This includes Dell selling directly to customers and delivering PCs that the customer wants. Dell was a pure hardware vendor until 2009 when it acquired Perot Systems. Dell then entered the market for IT services. The company has expanded storage and networking systems. It is now expanding from offering computers only to delivering a range of technology for enterprise customers.