Sorry, I think the proper name is "Flash drive". USB flash drives are also known as "pen drives", "chip sticks", "thumb drives", "flash drives", "USB keys", and a wide variety of other names.
They are also sometimes called memory sticks, which is possibly a bad idea leading to confusion, because "memory stick" happens to be a Sony trademark describing their proprietary memory card system.
A USB flash drive is flash memory integrated with a USB 1.1 or 2.0 interface. It is a small, lightweight, removable and rewritable data storage device. The flash drive is a very fast memory device that is more reliable than a floppy drive.
Find out here how to make one bootable
Bootable Flash Drives