In a kitchen the hob is a projection, shelf, grate or bench for holding food or utensils at the back or side of a hearth

Hearth

In common historic and modern usage, a hearth is a brick- or stone-lined fireplace or oven often used for cooking and/or heating. For centuries, the hearth was considered an integral part of a home, often its central or most important feature...

 (fireplace

Fireplace

A fireplace is an architectural structure to contain a fire for heating and, especially historically, for cooking. A fire is contained in a firebox or firepit; a chimney or other flue allows gas and particulate exhaust to escape...

) to keep them warm, or an internal chimney-corner. In modern British English

British English

British English, or English , is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere...

 usage, the word refers to a cooktop or hotplate, as distinguished from an oven

Oven

An oven is a thermally insulated chamber used for the heating, baking or drying of a substance. It is most commonly used for cooking. Kilns, and furnaces are special-purpose ovens...

.

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  Ansley Wilcox
  Ansley Wilcox was an American scholar, Oxford graduate, lawyer, civil service reform commissioner, New York political insider and friend of Theodore Roosevelt....
  
   Mansion.]

Etymology

The word is a noun meaning approximately "holder", derived from the Old English verb habban "to have, hold". The word hub "support of a disk or wheel" is apparently from the same source.