diff --git a/preface.asciidoc b/preface.asciidoc
index 82e962ce..5e5ec4dd 100644
--- a/preface.asciidoc
+++ b/preface.asciidoc
@@ -111,11 +111,11 @@ Watch us on YouTube: link:$$http://www.youtube.com/oreillymedia$$[]
 
 This quick glossary contains many of the terms used in relation to bitcoin. These terms are used throughout the book, so bookmark this for a quick reference and clarification.
 
-address (aka public key)::
+address (sometimes mistakenly referred to as a public key)::
 ((("bitcoin address")))
 ((("address", see="bitcoin address")))
 ((("public key", see="bitcoin address")))
-	A bitcoin address looks like +1DSrfJdB2AnWaFNgSbv3MZC2m74996JafV+, they always start with a one. You can have as many as you like, share them so people can send you coins. 
+	A bitcoin address is derived from a public key, and looks like +1DSrfJdB2AnWaFNgSbv3MZC2m74996JafV+. Most addresses begin with a one, excepting multisignature addresses, which begin with a three. You can have as many as you like, share them so people can send you coins.
 
 bitcoin::
 ((("bitcoin")))