A webcast is a media file distributed over the Internet using streaming media technology. A webcast may either be distributed live or on demand.A webcast uses streaming media technology to take a single content source and distribute it to many simultaneous listeners/viewers.The term webcasting is usually reserved for referring to non-interactive linear streams or events. A wedcast is a webcast of a wedding  It allows family and friends of the couple to watch the wedding in real time on the internet.