This short introduction 3 part OVA is essentially the survival kit for the world of Mahouka Koukou no Rettousei.
The world of the magic high school is quite a blur for those who just jumps into the anime without background knowledge from reading either the Light Novel (LN) or read the manga previously. Those who did will know of the explanation of the world structure & magitek are mighty complex, which will make or break those who want to watch the series anime.
It's nice to now the company behind Mahouka do this extra little introduction (via moeified characters) doing some basic explanation vs. just leaving
them out (*cough*SAO*cough*) or making the main series drag by information overload.
I however, recommend only for those who haven't been introduced to the world of Mahouka Koukou no Rettousei beforehand. For the fellow LN or manga readers, feel free to jump right into the main series.