diff --git a/rpn.go b/rpn.go
index 164db2a..648a79e 100644
--- a/rpn.go
+++ b/rpn.go
@@ -115,6 +115,22 @@ DESCRIPTION
 
     You can use the shift command to remove the last number from the stack.
 
+  BUILTIN OPERATORS AND FUNCTIONS
+    Basic operators: + - x /
+
+    Math functions:
+
+        sqrt                 square root
+        mod                  remainder of division (alias: remainder)
+        max                  batch mode only: max of all values
+        min                  batch mode only: min of all values
+        mean                 batch mode only: mean of all values (alias: avg)
+        median               batch mode only: median of all values
+        %                    percent
+        %-                   substract percent
+        %+                   add percent
+        ^                    power
+
 EXTENDING RPN USING LUA
     You can use a lua script with lua functions to extend the calculator. By
     default the tool looks for "~/.rpn.lua". You can also specify a script
diff --git a/rpn.pod b/rpn.pod
index 1dea393..994695f 100644
--- a/rpn.pod
+++ b/rpn.pod
@@ -121,6 +121,22 @@ The stack can be reversed using the B<reverse> command.
 You can use the B<shift> command to remove the last number from the
 stack.
 
+=head2 BUILTIN OPERATORS AND FUNCTIONS
+
+Basic operators: + - x /
+
+Math functions:
+
+    sqrt                 square root
+    mod                  remainder of division (alias: remainder)
+    max                  batch mode only: max of all values
+    min                  batch mode only: min of all values
+    mean                 batch mode only: mean of all values (alias: avg)
+    median               batch mode only: median of all values
+    %                    percent
+    %-                   substract percent
+    %+                   add percent
+    ^                    power
 
 =head1 EXTENDING RPN USING LUA