A computer only needs one operating system to work. But what if you just want to try out a new system? Do you need to forget about the old one and erase your hard drive? No, you can have as many operating systems on your computer as you wish.
Linux requires 2 partitions to work. Partitions are sections of the hard drive. When you install Linux, it will provide a program called fdisk or disk druid allowing you to create the needed partitions. The main problems people have is that they don't have empty partitions to use for Linux, and they don't want to erase the current Windows or DOS partition. The trick is to resize your current partition to create empty space. Then you will be able to make the partitions needed by Linux to install properly. Fdisk doesn't allow you to resize a partition. You will need to use another program to do the job, before using fdisk to create the Linux partitions. A very popular commercial product to do this is Partition Magic from
http://www.powerquest.com.
Let's see step by step what is needed to resize an existing partition to allow the creation of a new one for
Linux:
Buy Partition Magic, or get any other tool that can safely resize partitions.
Make sure you have at least 150 megs free on your main partition, the required amount for
Linux.
Resize the partitions so you have at least 150 megs free, outside of any current partition.
Reboot and launch the Linux installation.
Run fdisk or any partitioning program that comes with the Linux distribution, and follow the installation instructions to make the required Linux partitions.

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