DaDesktop is a Virtual Classroom
A virtual classroom is a software tool where instructors and participants engage with each other and with the learning material. The difference with other video conferencing tools is that DaDesktop offer an added set of features that are essential to a learning environment like remote desktops designed for IT related training.
For example, if you use traditional video conferencing, the only way you could help your participant is via sharing or controlling their screen. In DaDesktop you provide every participant with a machine prepared specially for them, close to their location to minimize lag and to allow the trainer to control it whenever participant requests it.
Apart of the above DaDesktop allow you to record actions of trainer and each participant. Video conferencing software cannot record each participant desktops.