On Chanukah, we celebrate with parties, although there is no mitzvah obligation to do so. The source for the feasts comes from the celebration of the completion of building the mishkan. Although the mishkan was finished on Chanukah, it did not come into use until Nissan. Chanukah comes at the darkest point in the year, and the only way to recognize the nes (miracle) is if one watches it for all eight days. Our survival in golus (exile) is a miracle like this, too, and we wait for the day when we will have a complete revelation of Hashem's presence, just like at the inauguration of the mishkan.