Four different media technologies that come to mind are the following:
Internet-The internet is absolutely, to me, the most viable means of expressing an outlet on divulging a certain topic and/or subject that is being expressed to an audience. The internet is, hands down, the best way of reaching a broad group of people of all ages on a topic of discussion and a main method of reaching to those respective audiences.
Television-This method of media has been around for several years as a mean of reaching the audience and optimal attention for the product/service/subject that is being discussed.
Publications- Periodicals, newspapers, magazines are also an excellent means of reaching a specific audience. It is sometimes speculated that publications are somewhat of an outdated method of reaching an audience because of it's history of being the method of reaching audiences for many years. There are still individuals that rely on publications as their primary means of knowing what is happening in the world, thus making it a viable means of media technology.
Radio-We listen to radio in the car, at work, or even at home. Several companies use the radio as a way of reaching the an audience to advertise a product because of it's inevitable usage. By inevitable, I mean the fact that, for example, when turning on your car, it is automatic, in most cases, that the radio comes on simultaneously. So, in other words, the audience is reached, which is what the advertiser intended.