Introduction Your computer's storage space is limited. You can't use more memory and disk space than you have available.
Storage space is shared among programs.
If you receive so much e-mail that your disk fills up, for example, you won't be able to save a new file from your word processor. This might happen by accident, or an attacker might deliberately flood you with mail. You can partition your space to protect one program from another. For example, you can set aside one disk for receiving mail, and another disk for word processing. Under most operating systems, when you install a new disk, you can chop it into several limited partitions.