Most modern versions use those icons to represent the appliance's various cooking modes. As such, it's a good idea to brush up on your knowledge of oven symbols, since most of them look the same in the majority of these appliances. Now, the oven symbols inside that square change, showing numerous cooking modes and heating options. Another common oven symbol is the one with a fan icon in the square. You can also encounter a mix of the fan symbol and the horizontal line, which means those settings are working together at the same time.