A floppy disk was a thin, square piece of plastic used to store computer files before USB drives and cloud storage were common. Despite its name, the disk itself wasn't actually floppy: it was protected by a rigid plastic case about the size of a sticky note. The “floppy” part was the magnetic disk hidden inside the case, which bent easily if you removed it (though you weren't supposed to).

Floppy disks were extremely important in computing history. Throughout the 1980s and 1990s, people used them to save documents, transfer files between computers, and install software. A typical floppy disk could hold about 1.4 megabytes of data, which sounds like a lot until you realize that a single photo from a modern phone uses more space than that. You'd need about 700 floppy disks to hold the information on one CD.

The floppy disk drive was the slot in a computer where you inserted these disks. When you pushed a disk in, the computer could read the files stored on it or save new files to it. You had to be careful: floppy disks could be erased by magnets and damaged by heat, dust, or simply bending them the wrong way.

By the early 2000s, floppy disks became obsolete as CDs, USB drives, and internet file sharing took over. Today, many computers don't even have floppy disk drives. Interestingly, the “save” icon in many programs still looks like a floppy disk, even though most young people have never seen or used one.