text: when the classes have videos they can put back the video over and over, when ever they want, how many times they want, where ever they want,if they want the teacher to do not talk fast or to do it they can regulate that also, they save a lot of money, because they do not have to spend a lot of money in materials, like for posters and things like that, they do not have to be with some people that distract them from the classes and is also faster to get the classes done.