1) An introductory discourse 2) Brief introduction 3) Intro 4) Introduction 5) Introduction or preface 6) Introductory discourse 7) Literary intro 8) Preamble 9) Preface 10) Prelude 1) Intro 
preface
• (v. t.) To preface. • (n.) Preface; introduction; preliminary observations; prelude.
Pro'em noun [ Latin prooemium , Greek ...; ... before + ... way, course or strain of a song: confer French proème .] Preface; introduction; preliminary observations; prelude. « Thus much may serve by way of proem .» Swift. Pro'em transitive verb To preface. [ Obsolete] South. 
proem 1. A short introduction or preface. 2. An introduction to a literary work or a speech. 3. Etymology: from Greek pro-, 'before' plus oime, 'song'.
an introductory discourse; introduction; preface; preamble.