I have a windows 8.1 and I would like to know how to install ubuntu 13.10 on it? I have tried numerous times with no success. And can you please explain it in the simplest terms.
By on it do you mean virtual Machine or dual boot?
For Dual boot download the distribution you wish to install. You need one or two empty partitions on your hard drive. Place the installation files on a USB (have to make it bootable) or CD and boot from it. Install on the empty partition (format of course)
For Virtual Machine. Download your virtual machine or choice. Open it and add new virtual machine. Add the distro file to your machine and load it.
I personally use VMware on my desktop and have only Xubuntu on my laptop. (need the windows for Games)