Floppies make it possible to backup important information in case it is lost by the computer. RAM loses its memory each time the computer is turned off, but ROM keeps information stored even when the computer is not turned on. Well, sometimes computers have problems that can cause them to crash . A crash is something that happens inside the computer's circuits and can make it forget things. Having important information backed up on disks will allow you to put it back into your computer's memory.
Disks also allow information to be transferred between different computers.
Let's say that you are working on a project using a computer at the library, but you don't finish it by closing time. There's your project sitting in the computer. You write the information to a disk, take it home and upload the information into your computer from the disk. You move the program into your computer's memory by installing it. Some programs are transferred completely into your computer's hard drive.