- Shevut – A Rabbinic ordinance, like climbing a tree or riding an animal
- Reshut – Something that is not always a mitzva, although it is certainly a good deed, like getting married or trying a court case
- Mitzva – Actually fulfilling a commandment, like putting aside tithes or consecrating an object to the Temple
All of these activities are forbidden by Rabbinic ordinance lest they lead to forbidden activities or because they appear very similar to weekday activities.
The commentaries discuss why there is a need to create divisions between different types of Rabbinic prohibitions, given that the bottom line is that they are all forbidden on both Shabbat and Yom Tov. One approach is taken by Rabbeinu Tam who argues that there are real differences between the cases, and that the Mishna is only discussing cases where the activity is not truly obligatory. If, however, a mitzva will really be fulfilled by this action, then the Sages would permit the mitzva to be done on Yom Tov. Some suggest that even according to Rashi we will distinguish between the different categories in a case where the act is performed bein ha-shemashot – in the moment when it is still questionable whether the holiday has begun or not. At that moment we will be lenient and allow those activities that are mitzvot to be done.
The Hatam Sofer argues that the Mishna must be understood to be saying that these activities are forbidden if they are shevut or reshut from the perspective of the person doing them. If, however, they are being done as a mitzva, the rule of the Mishna may not apply.