it means that the food is ready.

a meal is to prepare food and tableware for the guests who have ordered the meal. The diner must know the color, fragrance, taste and shape of the product, and refuse to dine when unqualified products and utensils are found to be incomplete and unclean. Learn to ask for help and about giving help when eating. Meal delivery personnel don't need to deliver the products to the guests in person, but can give them to the regional person in charge. If the regional person in charge is not busy, when they see the products delivered, they should quickly take the products and deliver them to the guests' table.