What is the old cooking plate that went under kettles?

Here's some more information:

* Hobs were typically made of cast iron or other heat-resistant materials.

* They were placed directly over a fire source, like a wood-burning stove or open hearth.

* The kettle would sit on top of the hob, allowing the heat to transfer and bring the water to a boil.

* Hobs are a bit of a throwback to a time before modern gas and electric stoves became common.

While not as common today, some people still use hobs for traditional cooking or as a more rustic option.