Answer:
Shabbat is the Jewish Sabbath and the day of rest. Shabbat is the 7th day of the week and starts Friday sundown and ends Saturday sundown.
We welcome shabbat in by lighting shabbat candles and reciting blessings over the candles, wine, and challah (traditional bread). This is followed by a family meal that normally incorporates two different types of meat (unless the individuals are vegetarian).
During shabbat, all 39 categories of work are avoided, this includes such things as creating (writing, turning on lights, lighting fires, carrying items outside the home, cooking, etc). Time is spent with family and friends and religious services are attended in synagogue. Because cooking is not allowed, dishes that are made in advance are kept warm to be eaten for lunch on Saturday, a traditional dish that's eaten is cholent.
There is a special religious service called 'Havdalah' at the end of shabbat were we say good by to shabbat and welcome in the new week.