Shabbosthe Sabbath, the weekly holiday that commemorates the day of rest that God took after creating the world in six days. Shabbos begins at sundown on Friday night with the lighting of candles, the blessing of wine and the saying of prayers. Afterwards a festive meal is eaten. Shabbos ends with nightfall on Saturday. No work can be performed, and the day is to be spent in rest and prayer.
Source: Binyomin Kaplan.