The main storage devices for computers are: CD’s(on occasion), flash drive, the computers own memory, and the latest is the Internet based “cloud”. The type needed for every person depends upon what you will use it for. I personally use flash drives. I have a few that I keep handy. I back up all my files this way. I, also, use the computer’s own memory, but always have a backup. There is one that I did not mention, which comes with my new laptop. I bought a Dell and they offer a free one year use of there back up recovery. This runs as you schedule it and will back up your computer.
I found a website for the “cloud”. http://www.top10cloudstorage.com/cloud-storage/
This site offers a review of pricing and usage of the top ten cloud companies. This site also gives you a chance to review each of them with a site link. However, be prepared to pay. Free is not an option with this brand of technology. Maybe someday with the ever changing world of technology. Wishful thinking.