Hearth

A hearth (har-th) is a brick or stone lined fireplace or oven that is used for cooking and heating. Historically, the hearth was the center of the home, as it provided heat for the house. Its Latin name is "focus". That is why "focus" is used for many kinds of central point.
In more modern times, the hearth may be section of the fireplace that can be seen. This often includes tiles around the base of the fireplace and the floor.