As expected in a technology industry where several companies are actively pursuing market share, terminology can become confusing as each company tries to differentiate and brand themselves. This comes at the detriment to the user who has trouble figuring out the difference (if any) in these terms.
So, what is the difference between these terms? Nothing really. Webinars seem to be the leading term currently. Most people have either heard of a webinar or can deduce what they are from the meaning of its two root words: web and seminar. However, as these types of events become more popular a lot of companies do not want to be bound by the webinar nomenclature. Here at ReadyTalk, we call them Web Seminars. Some other companies refer to them as webcasts and others as web events. There may be subtle differences between the each term as each company tries to stress a different part of their service.
Webcasts tend to be one-way communication with little to no interaction between participant and speaker. Web Events tend to connote large important events like IR calls or earnings announcements. These events, like the webcasts, tend to have little interaction as well. Webinars and web seminars tend to be interactive like their more traditional counterpart - the seminar.
Your other options is too not worry about these terms and let ReadyTalk take care of your event!