Original HTML::Template is written by Sam Tregar, sam@tregar.com with
contributions of many people mentioned there. Their efforts caused
HTML::Template to be mature html template engine which separate perl code
and html design. Yet powerful, HTML::Template is slow, especially if
mod_perl isn't available or in case of disk usage and memory limitations.

HTML::Template::Pro is a fast lightweight C/Perl+XS reimplementation of
HTML::Template (as of 2.8) and HTML::Template::Expr (as of 0.0.5). It is
not intended to be a complete replacement, but to be a fast implementation
of HTML::Template if you don't need quering, the extended facility of
HTML::Template. Designed for heavy upload, resource limitations, absence of
mod_perl.

HTML::Template::Pro has complete support of filters and
HTML::Template::Expr's tag EXPR="<expression>", including user-defined
functions.