diff --git a/docs/api.md b/captcha.api.php
similarity index 83%
rename from docs/api.md
rename to captcha.api.php
index 195160f..5b3d5d3 100644
--- a/docs/api.md
+++ b/captcha.api.php
@@ -1,5 +1,7 @@
+<?php
 
-This documentation is for developers that want to implement their own
+
+/* This documentation is for developers that want to implement their own
 challenge type and integrate it with the base CAPTCHA module.
 
 
@@ -20,13 +22,13 @@ Functionality depends on the first argument $op:
       the form element where the user enters his answer.
     An optional additional argument $captcha_sid with the captcha session ID is
     available for more advanced challenges (e.g. the image CAPTCHA uses this
-    argument, see image_captcha_captcha()).
+    argument, see image_captcha_captcha()) and it is used for every session.
 
 Let's give a simple example to make this more clear.
 We create the challenge 'Foo CAPTCHA', which requires the user to
 enter "foo" in a textfield.
+ */
 
-"""
 /**
  * Implementation of hook_captcha().
  */
@@ -48,30 +50,10 @@ function foo_captcha_captcha($op, $captcha_type='') {
       break;
   }
 }
-"""
-
-Validation of the answer against the solution and other stuff is done by the
-base CAPTCHA module.
-
-
 
 
-=== Required: the .info file ===
-
-You should specify that your module depends on the base CAPTCHA module.
-Optionally you could put your module in the "Spam control" package.
-
-For our simple foo CAPTCHA module this would mean the following lines in the
-file foo_captcha.info:
-
-"""
-name = "Foo CAPTCHA"
-description = "The foo CAPTCHA requires the user to enter the word 'foo'."
-package = "Spam control"
-dependencies[] = captcha
-core = 6.x
-"""
-
+/* Validation of the answer against the solution and other stuff is done by the
+base CAPTCHA module.
 
 
 
@@ -81,9 +63,9 @@ More advanced CAPTCHA modules probably want some configuration page.
 To integrate nicely with the base CAPTCHA module you should offer your
 configuration page as a MENU_LOCAL_TASK menu entry under 'admin/config/people/captcha/'.
 
-For our simple foo CAPTCHA module this would mean:
+For our simple foo CAPTCHA module this would mean: */
+
 
-"""
 /**
  * Implementation of hook_menu().
  */
@@ -99,9 +81,9 @@ function foo_captcha_menu($may_cache) {
   }
   return $items;
 }
-"""
 
-You should of course implement a function foo_captcha_settings_form() which
+
+/* You should of course implement a function foo_captcha_settings_form() which
 returns the form of your configuration page.
 
 
@@ -111,9 +93,9 @@ returns the form of your configuration page.
 To offer a description/explanation of your challenge, you can use the
 normal hook_help() system.
 
-For our simple foo CAPTCHA module this would mean:
+For our simple foo CAPTCHA module this would mean: */
+
 
-"""
 /**
  * Implementation of hook_help().
  */
@@ -123,17 +105,17 @@ function foo_captcha_help($route_name, RouteMatchInterface $route_match) {
       return '<p>'. t('This is a very simple challenge, which requires users to enter "foo" in a textfield.') .'</p>';
   }
 }
-"""
 
 
 
-=== Optional: custom response validation ===
+
+/* === Optional: custom response validation ===
 The CAPTCHA module provides an option for case sensitive and case insensitve
 validation of the responses. If this is not sufficient, you can provide
 your own validation function with the 'captcha_validate' field, illustrated
 by the following example:
+ */
 
-"""
 /**
  * Implementation of hook_captcha().
  */
@@ -162,18 +144,18 @@ function foo_captcha_captcha($op, $captcha_type='') {
 function foo_captcha_custom_validation($solution, $response) {
   return $response == "foo" || $response == "bar";
 }
-"""
 
-Previous example shows the basic usage for custom validation with only a $solution
+
+/* Previous example shows the basic usage for custom validation with only a $solution
 and $response argument, which should be sufficient for most CAPTCHA modules.
 More advanced CAPTCHA modules can also use extra provided arguments $element
-and $form_state:
-"""
+and $form_state: */
+
 function foo_captcha_custom_validation($solution, $response, $element, $form_state) {
   return $form_state['foo']['#bar'] = 'baz';
 }
-"""
-These extra arguments are the $element and $form_state arguments of the validation function
+
+/* These extra arguments are the $element and $form_state arguments of the validation function
 of the #captcha element. See captcha_validate() in captcha.module for more info about this.
 
 
@@ -195,7 +177,7 @@ associative arrays with the following fields:
     to this value.
 
 For example:
-"""
+
 /**
  * Implementation of hook_captcha_placement_map
  */
@@ -211,8 +193,9 @@ function hook_captcha_placement_map() {
     ],
   ];
 }
-"""
-This will place the CAPTCHA element
+
+/* This will place the CAPTCHA element
   - in the 'my_fancy_form' form inside the container $form['items']['buttons'],
     just before the element $form['items']['buttons']['sacebutton'].
   - in the 'another_form' form at the toplevel of the form, with a weight 34.
+ */