Daf Yomi - Beitza 29- Lekavod Shabbos

The Mishnah records certain actions that one should not perform on Yom Tov in their usual manner so that the actions are distinguished from weekday activities. Weekday activities are referred to as עובדא דחול. The word חול, besides meaning mundane, also means sand. Sand functions to create a barrier between the sea and dry land. Similarly, Shabbos and Yom Tov serve as a barrier from the mundane, as on Shabbos and Yom Tov one can experience true holiness.