POST and GET data for use within a Plugin

I am trying to write a plugin that will use GET or POST data.

Can somebody give me some insight as to what classes I would use to

to be able to have my plugin use $_GET and $_POST variables via forms.

I already know I can’t use those variables directly so I am just looking for some insight on how to accomplish this.

Any help would be greatly appreciated…thanks in advance.

See the doc in http://piwik.org/docs/plugins/
more specifically, see http://piwik.org/docs/plugins/security-checklist/