How to install Ubuntu and Windows on portable hard disk

[Itsme]

I have never installed any OS on my Portable Hard Drives. Therefore I wanted to try out, so if anyone could tell me how to install opertaing system on portable hard disk it would be great. I want to install a dual boot of Windows XP and Ubuntu or maybe any other Linux on the portable HDD. If I connect the poratable hard disk then wil it give the option to choose which os to boot in the laptop? Thank you

[newtech]

You can install the Operating System on your portable hard drive and then run it from set up when you turn your laptop on or create a dual boot system with your portable drive as a parchment with an assinged letter. If your laptop or computer supports booting from a USB device, (assuming you have an external USB hard drive) it shouldn't be too much of a problem in my view. Just install the OS on it, as you would normally do. It will probably be really slow though, since it's just USB.

[Zachary]

Yes, you can install OS on your portable hdd, but it might have to be a big thumb drive, enough to hold the OS. One downside though is it is kinda slow because the read/write on a thumb drive is not as fast as a hard drive. But I think that it wont be 100% as fast as with the internal hard disk but,it has to be over 8 gb,so itll be a hard drive portable.

[Team Leader]

It all also depends on the BIOS of your PC or Laptop ,so please note that even if your BIOS supports usb booting, you will need additional software to be installed. Even i tried this option and when it came to selecting the partition on the external hdd, windows gave an explaination saying that this was not supported and some additional drivers had to be installed.