Drupal has hooks, one of then is called hook_node_view which allows you to inject variables into your node templates. In order to actually modify the node with the content variables… done like so:

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$node->content[‘variable’] = ‘new var’;
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You need to actually return the $node variable from the hook function.

[php]
//mymodule.module
function mymodule_node_view($node, $view_mode, $langcod){
if($node->type == ‘content_type’){

$node->content[‘variable’] = ‘new var’;
return $node;
}

}
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You can then use the variable in your node template.

[php]
//node–content-type.tpl.php
print $content[‘variable’];

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