diff --git a/src/init.c b/src/init.c
index d7a8b445..9d50cf9c 100644
--- a/src/init.c
+++ b/src/init.c
@@ -33,14 +33,15 @@
 #include <stdarg.h>
 
 
+// The three global variables below comprise all global data in GLFW, except for
+// various static const translation tables.  Any other global variable is a bug.
+
 // Global state shared between compilation units of GLFW
 // These are documented in internal.h
 //
 GLboolean _glfwInitialized = GL_FALSE;
 _GLFWlibrary _glfw;
 
-
-// The current error callback
 // This is outside of _glfw so it can be initialized and usable before
 // glfwInit is called, which lets that function report errors
 //