advertising vs promotion

advertising and promotion both are nouns.

Word	Noun	Adjective	Verb	Adverb
advertising	Yes	No	No	No
promotion	Yes	No	No	No

As nouns, promotion is a hypernym of advertising; that is, promotion is a word with a broader meaning than advertising:

advertising: a public promotion of some product or service
promotion: a message issued in behalf of some product or cause or idea or person or institution

Other hypernyms of advertising include packaging, promo, promotional material, publicity.

advertising (noun)	promotion (noun)
the business of drawing public attention to goods and services	act of raising in rank or position
a public promotion of some product or service	the advancement of some enterprise
	a message issued in behalf of some product or cause or idea or person or institution
	encouragement of the progress or growth or acceptance of something