Will windows 8 operate on former windows 7 machine?

Can I upgrade my windows 7 machine to windows 8? I do not have a touch screen. Is there something else that I need.

It will most probably work, but I would :

a) Use the Windows 8 Upgrade Assistant to see what it reports.
http://www.eightforums.com/tutorials/11885-windows-8-upgrade-assistant-download-run.html

b) Check the manufacturer's website to see if they support Windows 8 on that model. It may be that you need a BIOS update (for instance some recent Dells need this) and they may have updated drivers and versions of software to make hot-keys work which are useful.

c) Before you start upgrading, make sure you have a full system image backup. Also if your Windows 7 system includes an option to make a Manufacturer's Recovery Disk, use it now. That way you can get back if something goes wrong (or you want to revert).

You don't need a touch screen to run Windows 8.

My Sony VAIO is prime example of it when I bought it 2 years ago it works well. My laptop is the nontouch and nonpen so its a normal one it I like it.

Its good to have because its basically two OS's in one and mostly use desktop apps but grown to use metro apps as well.

My old Dell Precision 370 runs Windows 8 very well.
X64, 3.4Ghz dual thread CPU, 4GB ram, 128GB SSD.