How do I install two Linux operating systems?

How do I install two Linux operating systems? -- Linux general technology-Linux technology and application information. For details, refer to the following section. One hard disk has a Fedora 8 Linux system installed and grub boot management program installed.
Install Fedora 9 in an idle partition as follows:
1. Place the Fedora-9-i386-DVD.iso file to the root directory of a Windows Fat32 partition (hd0, 4) and decompress the isolinux directory in this iso file to a more directory (hd0, 4 );
2. Go to the Fedora 8 Linux system and add the following content to the file/boot/grub. conf:
Title install linux FC9
Root (hd0, 4)
Kernel/isolinux/vmlinuz
Initrd/isolinux/initrd. img
3. Restart the machine and select [install linux FC9] to enable the Fedora9 installation program. When you need to select a media installation source, select the hard disk.
Note:
1. (hd0, 4) is the number of the hard disk partition of grub. hd indicates the hard disk. hd indicates both IDE and SCSI. 0 indicates the first hard disk and 4 indicates the fifth partition;
2. If grub is updated during the installation of Fedora9, the grub startup selection menu is subject to those in Fedora9. It is best to update grub because the grub STARTUP configuration parameters of Fedora9 are different from those of Fedora8. After entering the Fedora9 system, update the startup configuration parameters of Fedora8 from the original grub. conf to the grub. conf file in the Fedora9 file.