What is difference between Webcasting and webconferencing?

A webcast is a media presentation distributed over the Internet using streaming media technology to distribute a single content source to many simultaneous listeners/viewers. A webcast may either be distributed live or on demand. Essentially, webcasting is "broadcasting" over the Internet.

Web conferencing may be used as an umbrella term for various types of online collaborative services including web seminars ("webinars"), webcasts, and peer-level web meetings. It may also be used in a more narrow sense to refer only to the peer-level web meeting context, in an attempt to disambiguate it from the other types of collaborative sessions. Terminology related to these technologies is inexact, and no generally agreed upon source or standards organization exists to provide an established usage reference.

A webcast is like a broadcast. It is usually one person, or multiple people giving a presentation. There is not any interaction from the online audience who can be listening or watching video of the webcast. The best example is to think of it like a radio station broadcast over the internet or a television station simulcast.

A web conference is similar to a regular conference or convention, but is held over the internet rather than in person. The difference from a webcast is that a web conference is more like a meeting online. Sound, video and even computer screens can be shared between the attendees and depending on the conferencing software, the members may all call into one phone line to speak to each other if that is not an option over the computers. Online web conferencing allows for interaction between presenters and attendees. Different settings can be enabled to allow conference members to take turns speaking and sharing information.