An oven is a tool that is used to expose materials to a hot environment. Ovens contain a hollow chamber and provide a means of heating the chamber in a controlled way. In use since antiquity, they have been used to accomplish a wide variety of tasks requiring controlled heating. Because they are used for a variety of purposes, there are many different types of ovens. These types differ depending on their intended purpose and based upon how they generate heat.

Ovens are often used for cooking, usually baking, sometimes broiling; they can be used to heat food to a desired temperature. Ovens are also used in the manufacturing of ceramics and pottery; these ovens are sometimes referred to as kilns. Metallurgical furnaces are ovens used in the manufacturing of metals, while glass furnaces are ovens used to produce glass.

There are many methods by which different types of ovens produce heat. Some ovens heat materials using the combustion of a fuel, such as wood, coal, or natural gas, while many employ electricity. Microwave ovens heat materials by exposing them to microwave radiation, while electric ovens and electric furnaces heat materials using resistive heating. Some ovens use forced convection, the movement of gases inside the heating chamber, to enhance the heating process, or, in some cases, to change the properties of the material being heated, such as in the Bessemer method of steel production.

The earliest ovens were found in Central Europe and date back to 29,000 BC. They were roasting and boiling pits inside yurts used to cook mammoth. In Ukraine from 20,000 BC they used pits with hot coals covered in ashes. Food was wrapped in leaves and set on top, then covered with earth. In camps found in Mezhirich, each mammoth bone house had a hearth used for heating and cooking. Ovens were used by cultures who lived in the Indus Valley and in pre-dynastic Egypt. By 3200 BC, each mud-brick house had an oven in settlements across the Indus Valley. Ovens were used to cook food and to make bricks. Pre-dynastic civilizations in Egypt used kilns around 5000–4000 BC to make pottery.

Tandır ovens used to bake unleavened flatbread were common in Anatolia during the Seljuk and Ottoman eras and have been found at archaeological sites distributed across the Middle East. The word tandır comes from the Akkadian tinuru, which becomes tanur in Hebrew and Arabic, and tandır in Turkish. Of the hundreds of bread varieties known from cuneiform sources, unleavened tinuru bread was made by adhering bread to the side walls of a heated cylindrical oven. This type of bread is still central to rural food culture in this part of the world, reflected by the local folklore, in which a young man and woman sharing fresh tandır bread is a symbol of young love. However, the culture of traditional bread baking is changing with younger generations, especially with those who reside in towns and prefer modern conveniences.

During the Middle Ages, instead of earth and ceramic ovens, Europeans used fireplaces in conjunction with large cauldrons. These were similar to the Dutch oven. After the Middle Ages, ovens underwent many changes over time from wood, iron, coal, gas, and even electric. Each design had its own motivation and purpose. The wood-burning stoves saw improvement through the addition of fire chambers that allowed better containment and release of smoke. Another recognizable oven would be the cast-iron stove. These were first used around the early 1700s, when they themselves underwent several variations including the Stewart Oberlin iron stove that was smaller and had its own chimney.

In the early part of the 19th century, the coal oven was developed. It was cylindrical in shape and made of heavy cast iron. The gas oven saw its first use as early as the beginning of the 19th century as well. Gas stoves became very common household ovens once gas lines were available to most houses and neighborhoods. James Sharp patented one of the first gas stoves in 1826. Other improvements to the gas stove included the AGA cooker, invented in 1922 by Gustaf Dalén. The first electric ovens were invented in the very late 19th century; however, like many electrical inventions destined for commercial use, mass ownership of electrical ovens could not be a reality until a better and more efficient use of electricity was available.

Over time, new cooking methods have been developed. The microwave as a cooking tool was discovered by Percy Spencer in 1946, and with help from engineers, the microwave oven was patented. The microwave oven uses microwave radiation to excite water molecules in food, causing friction and thus producing heat.