diff --git a/01-intro/Makefile b/01-prelim/Makefile
similarity index 100%
rename from 01-intro/Makefile
rename to 01-prelim/Makefile
diff --git a/01-intro/intro.tex b/01-prelim/prelim.tex
similarity index 99%
rename from 01-intro/intro.tex
rename to 01-prelim/prelim.tex
index 978cbd98ddba6cbf459f173341efe10a5848aeec..59856add9a79880cd3c59afec917c01c035054fc 100644
--- a/01-intro/intro.tex
+++ b/01-prelim/prelim.tex
@@ -11,9 +11,7 @@
 \noalign{\vskip-\smallskipamount}
 }}$$}
 
-\chapter[intro]{Introduction}
-
-\section{Examples of data structures}
+\chapter[prelim]{Preliminaries}
 
 Generally, a~data structure is a~``black box'', which contains some data and
 allows \df{operations} on the data. Some operations are \em{queries} on the current
@@ -27,6 +25,8 @@ We usually separate the \df{interface} of the structure (i.e., the set of operat
 supported and their semantics) from its \df{implementation} (i.e., the layout of data
 in memory and procedures handling the operations).
 
+\section{Examples of data structures}
+
 \subsection{Queues and stacks}
 
 A~\df{queue} is a~sequence of items, which supports the following