"I have all the information saved on my hard drive."
"I finished the presentation preparation and I saved it on my hard drive."
"I have the documents you are looking for saved on my computer."
"I have the information on my computer. Do you want me to put it on a floppy disk for you?"

When you say something like, 'saved on my computer', it is understood that you are referring to the hard drive, so in this situation, you can use the two words interchangeably.

"I'm running out of room on my hard drive."
"I need a bigger hard drive."

"I have the information on my computer, but I think I will need to prepare hard copies for the meeting."

Hard copy refers to something that is tangible. For example, a hard copy of a report is a printed out version on paper. A soft copy is the file stored on the computer.