A USB flash drive is a compact, portable storage device that plugs into a USB port to quickly store, transfer, and back up digital files such as documents, photos, videos, and software. It uses solid-state flash memory, meaning it has no moving parts, which makes it durable, lightweight, and resistant to shock. Compatible with most computers, laptops, and many other electronic devices, a USB flash drive offers a convenient plug-and-play solution for everyday data storage and sharing.