U3 technology was developed jointly by SanDisk and M-Systems and is an open-standard. SanDisk later acquired M-Systems (2006).

The technology relies upon a tiny 4MB read-only partition which behaves much like a CD-ROM drive, while the data partition shows up as a regular flash drive – simple enough. Windows is tricked into treating the system partition as a CD – hence, U3 takes advantage of Windows AutoPlay whereby Windows automatically runs the U3 LaunchPad, requests the user password, and if all passes muster, unlocks the data partition of the drive.

The best part about it is that U3 will run on anyone’s PC – including in Internet cafes – whether or not the user has Administrative rights!

The LaunchPad is the main interface of the U3 smart drive, and it looks a lot like your standard Windows XP menu. There is a U3 icon in the system tray, so you can just open or manage applications and documents on the U3 USB drive from there.