Difference between volitile memory and non-volitile memory?

If you computer has volitile memory, the RAM gets erased every time you turn off your computer. If it had non-volitile memory, it would save information in it. You can get similar effects by 'hybernating' your computer rather than shutting it down completely. It keeps about 10 watts of electricity going to the memory to save the info. Traditionally, devices such as PDA's primarily use non-volitile, while PC's use volitle. New developments in quantum spintronics may make non-volitile memory standard in home computers and laptops fairly soon.