A webcast is a non-interactive presentation, broadcast over the internet to many simultaneous listeners or viewers. A webcast may either be distributed live or on demand. The transmission is one-way and does not allow interaction between the presenter and the audience.
A webcast might be just a simple audio stream or it might include visual aids such as PowerPoint slides, recorded video clips, or live software demonstrations.
Webcasts are often used by large public companies to broadcast the audio from their investor calls each quarter, to review their financial results and provide a commentary from management. Some sports teams now webcast their games, and special events such as fashion shows may be webcast with live video and audio.