If I create a proper LiveCD and run the OS from the disc does it save any information on a hard-drive or is it ALL saved to the PC's memory? I've looked around for a clear, direct "yes/no" answer to this question but I can't seem find it anywhere. Common sense would say yes but you never know and what I need to do requires an OS that does not use Flash(usb) or Magnetic(hd) storage of any kind while in operation.
From the answers to this question, we can safely believe that no data is stored on the hard disk unless we choose to save it to hard disk(persistence).
As for a definitve answer check out this post on stackoverflow which explains that it is a
Quoting from the Stackoverflow answer to the above said question:
For more detailed information regarding this, check out the Wikipedia article on Live Cd explaining the
Booting an Ubuntu live session from a live CD will not be able to write data on a harddrive unless the drive was mounted.
But there is a caveat to this in case you are concerned about data security issues.
If you boot your live CD on a system with an existing swap partition the live environment may also use this as swap. We therefore have to disable swap after booting the live environment. See this question on how to do this: