The Upload class is a wrapper for uploading files using html forms. The form should have the 'enctype="multipart/form-data"' attribute for this the files to be uploaded properly. The Class should be created by passing $HTTP_POST_FILES as the only argument for the constructor (e.g. $upload = new Upload(&$HTTP_POST_FILES)), and also by reference (the & indicates this). See http://www.sloppycode.net/sloppycode/PHP/cm13.html for the manual.