A gas-on-glass cooktop has gas burners on the cooktop. The biggest advantage of a built-in gas cooktop is that you only need to clean one smooth surface after cooking. When you spill your tomato sauce during cooking, the stains won't burn on the cooktop. The gas burners have their own pan support that you remove before cleaning it. Gas-on-glass built-in cooktops are often black, giving them a sleek and robust appearance. They fit well in an industrial, modern kitchen.