Two portable kinds of storage are the floppy disk and the CD-ROM disk . When you buy a computer game, a writing program, or any other kind of computer program, it's usually stored on a floppy disk or a CD-ROM disk. You might also use these disks to store back-up copies of files from your computer. You can read and write information to a floppy disk using a hardware device called the floppy drive . The CD-ROM disk stores information optically.
Information is read by a CD-ROM player , using laser light.
Once information is written to a CD-ROM disk, it's permanently stored on the disk. If you want to copy a program from a floppy disk onto your computer, the information is stored on your hard drive , which can have lots more storage room than a floppy disk. You can read and write information to the hard drive. The information is stored in the coating of the drive's disks, in patterns of magnetic particles. This information is saved even when you turn off the computer.