preface vs introduction

preface and introduction both are nouns.

Word	Noun	Adjective	Verb	Adverb
preface	Yes	No	Yes	No
introduction	Yes	No	No	No

As nouns, introduction is a hypernym of preface; that is, introduction is a word with a broader meaning than preface:

preface (noun)	introduction (noun)
a short introductory essay preceding the text of a book	the act of putting one thing into another
	the act of beginning something new
	the act of starting something for the first time; introducing something new
	the first section of a communication
	formally making a person known to another or to the public
	a basic or elementary instructional text
	a new proposal

preface (verb)	introduction (verb)
furnish with a preface or introduction