A chafing dish is a portable serving dish that uses a heat source, often a candle or another type of fuel, to maintain the temperature of the food.
The dishes in the image appear to be a type of round chafing dish with a decorative, gold-trimmed lid.
The setup includes a variety of salads and other dishes, suggesting a catering event like a wedding or large party.
Chafing dishes are commonly used by professional caterers and for home use to serve a variety of dishes, from appetizers to main courses.