diff --git a/Doc/lib/libmain.tex b/Doc/lib/libmain.tex
index 39edfd7..949d2b2 100644
--- a/Doc/lib/libmain.tex
+++ b/Doc/lib/libmain.tex
@@ -1,4 +1,5 @@
-\section{Built-in Module \module{__main__}}
+\section{\module{__main__} ---
+         Top-level script environment.}
 \declaremodule[main]{builtin}{__main__}
 
 \modulesynopsis{The environment where the top-level script is run.}