storage vs memory device

storage and memory device both are nouns.

Word	Noun	Adjective	Verb	Adverb
storage	Yes	No	No	No
memory device	Yes	No	No	No

As nouns, memory device is a hypernym of storage; that is, memory device is a word with a broader meaning than storage:

Other hypernyms of storage include computer hardware, hardware, storage device.

storage (noun)	memory device (noun)
the commercial enterprise of storing goods and materials	a device that preserves information for retrieval
the act of storing something
depositing in a warehouse
a depository for goods
an electronic memory device
(computer science) the process of storing information in a computer memory or on a magnetic tape or disk