Some games and activities on Clifford's website use free applications or plug-ins to enhance the level of interactivity. These applications and plug-ins are listed below. Please note that not all of Clifford's activities require these plug-ins and that each of these can be downloaded free of charge.

RealPlayer streams audio and video files so that visitors can enjoy media experiences without waiting for the entire file to download.

Shockwave and Flash plug-ins allow visitors to experience animation and interactive multimedia games through a Web browser.