What is U3?

U3 refers to a proprietary application design specification created for Microsoft Windows operating systems so that applications can be executed directly from a specially formatted USB flash drive. Applications are allowed to write files or registry information to the host computer, but this information must be removed when the flash drive is ejected.

USB flash drives adhering to the U3 specification are termed "U3 smart drives" by U3.com. "U3 smart drives" differ from traditional USB flash drives because they come preinstalled with the U3 Launchpad, which emulates the Windows OS start menu, and controls program installation

Imagine carrying your favorite software, preferences, profiles and data on a device no bigger than a pack of gum. With a U3 smart drive, you can plug into any Windows 2000 or XP PC and work , play a game, message friends, send email, edit photos and more, all without worrying if applications are installed on the computer.

Storage+Software=Smart

Imagine carrying your software on the same flash drive that carries your files. That's what you can do with a U3 smart drive. You can plug it into any PC and work, play a game, message friends, send email, edit photos and more. A U3 smart drive makes any PC your own PC. And when you unplug it, it leaves no personal data behind.