back button - want to add one to more pages like prod listing

hi,

I want to create a back button on the prod list/prod info page .

Now I can get the c_path of the current link with $_GET['cPath'].

I can use a <a href... with the path to call worked out from looing up the db with the cpath. In prod list i can call the previous page by omitting the last paramter on another <a href ...call.
I can do it using a standard html/php solution.

How do I use the ZC way as it uses

zen_href_link(zen_get_info_page....
I don't know how to work these commands as i can't get any documentation on it.

I saw a zen_back() command , does that work?

I checked the wiki and google but i really can't get the information on how the zen..._link works.

I want to use zen.._link() but really would like some information on it and why you need it comapred to standard <a href..