There is normally a slight delay as the computer finds the right space on the hard drive and actually saves the information. As a result, it stays on the hard drive - regardless of whether you turn the computer off. The information stays there. And, later, you can erase your file and free up that space. Relatively Cheap Can turn off the computer, and reload the information later.
RAM comes in the form of computer chips.
These chips plug into special connectors in your computer. The purpose of these chips is to provide fast storage for the computer to use. This happens very quickly. Remember, the hard drive is a physical object that is spinning. Let's say you are typing in a Term Paper in your Word Processor.