diff --git a/README.md b/README.md
index 22e7344..6a5df9a 100644
--- a/README.md
+++ b/README.md
@@ -116,6 +116,39 @@ Out of box, this works:
 * Font.
 
 
+# Functions
+These are `pgplot` functions used by `skymap`.
+
+```
+cpgbox
+cpgcirc
+cpgconl
+cpgcont
+cpgcurs
+cpgdraw
+cpgend
+cpgeras
+cpgmove
+cpgmtxt
+cpgopen
+cpgpap
+cpgpt1
+cpgqch
+cpgqci
+cpgqls
+cpgrect
+cpgsch
+cpgsci
+cpgscr
+cpgsfs
+cpgsls
+cpgslw
+cpgsvp
+cpgtext
+cpgwnad
+```
+
+
 # Color
 Colors 1-15 are used in the color index, documented here: