How to display the node id as a field (with label) This question is really simple, i need to use the node id as an identifier and so i need to display it whenever a certain content type is shown. What's the best way to do this? 
i need to display the node with label and so on, i just don't want to make a custom field for something that's already a field.
Create a template for the content type and use &lt;?php print $node-&gt;nid; ?&gt;

Make a copy of node.tpl.php from modules/system and paste in your theme directory.  Copy the code from inside node.tpl.php and create a new file called "node--YOURTYPE.tpl.php" (replace YOURTYPE with the name of the content type).

Inside that file you can place &lt;?php print $node-&gt;nid; ?&gt; wherever you want the nid to be seen.  You can add a label, wrap it in HTML to style it, whatever you like. Save the file and clear the cache to see the changes.  Take a look at a node of that content type and you will see the node's nid.