Deprecated - Drupal core

I installed the gallery module and its great. i got everything working just like i wanted to. the website is doing wonderful. i increased our traffic and sales through the website by over 1,000 percent in about 2 1/2 months. I'm now working on getting us higher rankings on search engines without paying more for our google ADword or yahoo ADs. i installed xmlsitemap and its ok. but when i search for images on google we suck. i noticed that using the gallery module the title becomes the images alt as well. which is what most search engines index.

$node->content['myfield'] = array(
'#value' => theme('mymodule_myfield', $node->myfield),
'#weight' => 1,
);

what is myfield in above code and where it is defined in drupal. This code is on drupal.api for hook_view().

/**
* Implementation of hook_view().
*/
function course_view($node, $teaser = FALSE, $page = FALSE) {
$node = node_prepare($node, $teaser);
$node->content['course'] = array(
'#value' => theme('course_info', $node),
'#weight' => 1,
);
return $node;
}

I have written a simple code from drupal.api to show the node data created by user. The problem I am facing is that the data is inserting inside the database but hook view is not implementing the data showing capability.

My custom module have one form which is not displaying but permission and other things are working fine.

I am creating one module but in hook_access I have this warning message

warning: Missing argument 3 for course_access() in /var/www/project/drupaled/sites/all/modules/course/course.module on line 94.

http://drupal.org/node/17272

Where should I write the code on the above mention link ?
any idea