diff --git a/man5/charmap.5 b/man5/charmap.5
index 463e72d8d..de6e4a353 100644
--- a/man5/charmap.5
+++ b/man5/charmap.5
@@ -18,10 +18,12 @@
 .\"
 .TH CHARMAP 5 2014-06-02 "GNU" "Linux Programmer's Manual"
 .SH NAME
-charmap \- characters to define character sets
+charmap \- character set description file
 .SH DESCRIPTION
 A character set description (charmap) defines all available characters
 and their encodings in a character set.
+.BR localedef (1)
+can use charmaps to create locale variants for different character sets.
 .SS Syntax
 The charmap file starts with a header that may consist of the
 following keywords:
@@ -74,7 +76,13 @@ The character set definition section ends with the string
 The character set definition section may optionally be followed by a
 section to define widths of characters.
 .PP
-The width section starts with the keyword
+The
+.B WIDTH_DEFAULT
+keyword can be used to define the default width for all characters
+not explicitly listed.
+The default character width is 1.
+.PP
+The width section for individual characters starts with the keyword
 .B WIDTH
 in the first column.