The operating system, or OS, performs basic tasks like running software applications, files on your hard drive, and directing peripherals like a network adapters. The Apple OSX offers fewer hardware and software choices than Windows, but is often preferred by graphic and sound design professionals as well as among students and universities. The latest version of Windows, Microsoft Windows XP, comes included on many PCs on the market today. If you're going to a WLAN (for business use), Windows XP Pro may offer more operational flexibility. Other OS like Linux offer the experienced computer user more control, though the user-friendliness of these OS is not as advanced as Windows or OSX.