Navigation Bar

This is my code of navigation bar:

<div id="nav">

                <ul id="dropmenu">
                <li class="page_item <?php if ( is_home() ) { ?>current_page_item<?php } ?>"><a href="<?php bloginfo('url'); ?>">Home</a></li>
                <?php /* Navigation */
                	wp_list_pages('title_li=&depth=0&sort_column=menu_order&child_of=0');
                ?>
                </ul>

My query is that i want to display categories in place of pages at my website homepage ( https://jquery.co.gp) that is i want to replace
wp_list_pages to categories list.

Can any one help.

Thanks in advance