Common Noun:
* When used generically to refer to a type of publication, "magazine" is a common noun.
* Example: "I like to read magazines about travel."
Proper Noun:
* When referring to a specific, named magazine, "magazine" becomes part of a proper noun.
* Example: "I subscribe to National Geographic magazine."
Important Note:
* In the second example, "National Geographic" is the proper noun, while "magazine" functions as a descriptor.