Is keys a proper noun or common noun?

Answer 1

The noun 'keys' is a common noun, the plural form of the singular noun 'key'; a general word for a device used to open a lock; one of the operating buttons on a device (computer, typewriter, musical instrument, etc.); a set of musical notes based on a particular note; a list of symbols used to identify something on a map, a drawing, or operation manual; a list of answers to question in a test or text.

A proper noun is the name of a specific person, place, or thing; for example, Alicia Keys (American singer, songwriter) or Key West, Florida.

Answer 2

It can be either. If you key in data - it is a verb. If you use a key to open a door, it is a noun.

Answer 3

Common noun