Answer :

. => Primary Storage – is a computer memory that connects directly to the central processing unit of CPU. It is also known as RAM or random access memory. This storage do not permanently stores data because this is a volatile kind of storage.
=> Secondary storage – this may refer to storage that is non-volatile. Some examples of this storage are hard drive, CD/DVD, Flash drive, etc
=> offline storage – also known as tertiary storage. This is not a very known storage, this includes jukeboxes and tape libraries.