In this post I’ll briefly describe the steps I took to implement hAtom into my WordPress template.
hAtom is a draft specification for a Microformat to incorporate the common Atom format into HTML. Marking up your blog with those desciptive elements gives you several advantages but more on this later.

To make WordPress hAtom ready you have to edit the file named ‘Main Index Template’. The easiest way to do this is to go into the WordPress Admin and then to ‘Presentation’ -> ‘Theme Editor’.
This file includes the main ‘WordPress Loop’ that displays all of your posts. To add the hAtom Microformat here the only thing you have to do, is to set some HTML class attributes.

(Note: All examples taken from the “WordPress Default” template, edits are in bold)

Source: Optipelx 745 upgraded with Core 2 Duo Quad Q6600 2.4GHz – For Enterprise – Forum – For Enterprise – Dell Community