This package can be used to parse and filter insecure HTML tags and CSS styles. It comes with a general purpose markup parser class that can parse any type of markup documents like HTML, XML and DTD files. There are several other classes that can be chained together to retrieve the document token elements returned by the main markup parser class and filter the document elements in an useful way. The markup validator filter class validates a document against a DTD, eventually removing invalid tags and attributes. The safe HTML filter class processes HTML tags and data returned by the markup validator class and discards potentially harmful HTML tags and CSS that could be used to perform cross-site scripting (XSS) or cross-site request forgery (CSRF) security attacks. The HTML links filter class can extract the links contained in an HTML document. The DTD parser and CSS parser are utility classes used by the other classes.