Q:

How can I make a Triple boot

Currently I am using a dual boot with Windows7 and Ubuntu 12.04LTS.
I would like to try Windows8.
Not because I like it, but more and more people are using it.
I have created a partition where I would like to install it.
I have only one physical drive.
What should I do to create a triple-boot and don't mess up my Ubuntu?
This is my primary OS. But occasionally I need my Windows7.

A:

Install Windows 8 on a separate partition, then boot to Linux and update grub.  You'll then have Windows 8 added to the boot option.
$ update-grub

Updating grub will add all OS installations to the list.
Update:
I thought this was kind of elementary because this pop up all the time:
RecoveringUbuntuAfterInstallingWindows:

Boot to your Live Ubuntu CD
Install and run Boot-Repair
Click "Recommended Repair"
Now reboot your system.

I was initially more focus on the part where it's standard to have multiple boots.  If you have 10 partitions you can actually have an OS on each and updating grub will automatically add each to the boot menu.  YOu can even include USB drives or pen drives as some of those partitions.

