Any input or output equipment may be considered data storage equipment if it writes to and reads from a data storage medium. Data storage equipment uses either:
easily replaced
methods requiring mechanical disassembly tools
loss of memory if disconnected from the unit.
One of the most common mediums are----USB Flash Drives!!!
"Characteristics" of a USB Flash Drives aka Thumbdrives-
Light, Small, Portable, Rewritable, Uses USB port 2.0 the fastest USB port so far, Uses less power than Floppy disks and such, security is better than most other mediums too.
They also come in many different designs...^^