A kettle, sometimes called a tea kettle or teakettle, is a type of pot, typically metal, specialised for boiling water over a heat source, with a lid, spout and handle, or a small kitchen appliance of similar shape that functions in a self-contained manner. Kettles can be heated either by placing on a stove, or by their own internal electric heating element in the appliance versions.
A stovetop or hob kettle is a roughly pitcher shaped metal vessel used to heat water on a stovetop or hob. Kettles usually have a handle on top, a spout, and a lid. Sometimes stove-mounted kettles also have a steam whistle which indicates when the water has reached boiling point. In whistling tea kettles, when the steam build up in the container of the kettle tries to escape, it causes vibrations to occur within the chamber. As the speed of the releasing steam increases, the vibrations become louder, causing a whistle. Some whistling kettles have an actual whistle on a cover at the end of the spout.
The most popular of stovetop kettles are made with stainless steel. This is due to the lightweight nature of the kettle, in addition to the bright finish and durability. The crack-resistant nature of the kettle also makes it easier to clean. Kettles can also be made from copper, iron, aluminum, polished chrome or ceramic.
Electric kettles are normally constructed of durable plastic or steel (with a plastic handle) and powered by mains electricity. In modern designs, once the water has reached boiling, the kettle automatically deactivates, preventing the water from boiling away and damaging the heating element. Electric kettles were introduced as means to boil water without the necessity of a stove top.
In New Zealand and Australia, a kettle is colloquially referred to as a jug.