-default behavior. Currently only the mouse wheel buttons are supported. This is
-useful for disabling the scroll wheel action or running scripts that implement
-custom behavior for these buttons.
+default behavior. This is useful, e.g., for disabling the scroll wheel action
+or running scripts that implement custom behavior for these buttons.
+
+A button is always named +button<n>+, where 1 to 5 are default buttons as follows and higher
+numbers can be special buttons on devices offering more buttons:
+
+button1::
+ Left mouse button.
+button2::
+ Middle mouse button.
+button3::
+ Right mouse button.
+button4::
+ Scroll wheel up.
+button5::
+ Scroll wheel down.
+
+Please note that the old +wheel_up_cmd+ and +wheel_down_cmd+ commands are deprecated
+and will be removed in a future release. We strongly recommend using the more general
++bindsym+ with +button4+ and +button5+ instead.