From the HTML::Pager documentation:

DESCRIPTION

This module handles the paging of data coming from an arbitrary source and being displayed using HTML::Template and CGI.pm. It provides an interface to pages of data similar to many well-known sites, like altavista.digital.com or www.google.com.

This module uses HTML::Template to do all its HTML generation. While it is possible to use this module without directly using HTML::Template, it's not very useful. Modification of the look-and-feel as well as the functionality of the resulting HTML should all be done through HTML::Template objects. Take a look at HTML::Template for more info.