The primitive clay oven, or earthen oven / cob oven, has been used since ancient times by diverse cultures and societies, primarily for, but not exclusive to, baking before the invention of cast-iron stoves, and gas and electric ovens. The general build and shape of clay ovens were, mostly, common to all peoples, with only slight variations in size and in materials used to construct the oven. In primitive courtyards and farmhouses, earthen ovens were built on the ground.

In Arabian, Middle Eastern and North African societies, bread was often baked within a clay oven called in some Arabic dialects a tabun (also transliterated taboon, from the Arabic: طابون), or else in a clay oven called a tannour, and in other dialects mas'ad. The clay oven, synonymous with the Hebrew word tannour, lit. 'oven', was shaped like a truncated cone, with an opening either at the top or bottom from which to stoke the fire. Others were made cylindrical with an opening at the top. Built and used in ancient times as the family, neighbourhood, or village oven, clay ovens continue to be made in parts of the Middle East today.

The earthen oven has historically been used for baking flatbreads such as taftoon (Persian: تافتون), taboon bread and laffa, and has been in widespread use in the greater Middle East for centuries. Aside from baking, some were used for cooking: pots were laid within the cavity of the oven and set upon hot coals, covered in ashes. If the pots were intended to be left in the oven for an extended period of time (such as the night of the Sabbath day in Jewish culture where the food is left to cook until the next day), the opening at the top of the oven would be covered with a large, earthenware vessel. They would then add old rags around this vessel used to seal up the oven, in order to make the oven impervious to air around all the cooking pots. Where the opening was on the side, the door which covered the opening had to be left partially open to allow for combustion of the fire and coals during its initial lighting. The earthen oven differed slightly from earthen stoves and ranges where, in the case of the latter, the pots were laid directly over the stove and a fire stoked below.

Gustaf Dalman (1855–1941), describing the material culture of the Holy Land in the early 20th century, photographed several types of clay ovens which he saw in use there. Of those ovens used for baking bread, there was the tabun shaped like a large, bottomless earthenware pot turned upside down and fastened permanently to the ground. It has a pebbled floor made of either smooth beach pebbles or limestone pebbles. The pot-shaped contour was wider at the base and narrower at the top, where the opening was, used both for kindling the fire, and for inserting dough for baking. A second, similar type of oven had, in addition to the hole at the top, a second side opening called the "eye of the oven", used for stoking the fire and clearing away the ashes, and closed by a detachable door. This type had a ceramic floor. Both versions were equipped with a ceramic lid with a handle, used for covering and sealing the top opening (see illustration). These ovens were, typically, small in size and were placed within a baking hut to protect them from the elements. Some tabun ovens were "dug-ins", half built into the ground and half above-ground. Baking was made on the pebbled floor of the oven, after the bowl-like exterior wall of the clay oven that sat over the floor like an inverted cup had been covered, itself, with hot coals and embers scattered with ash, usually placed atop dried cattle dung.

The word tannour is often used in Hebrew (תנור) Persian (تَنور) and Arabic languages in a generic sense, meaning, a place where bread is baked by fire. In Yemen, the most common of clay ovens served both for baking and cooking. Its shape was cylindrical and reached half the height of man, and was made with a wide-open top, called the "mouth of the oven" (Arabic: bâb al-manaq), its top being uniform in diameter with that of the oven's base. Kindling was admitted through the opening in the top. A small air-hole was also made therein at the base of the oven, called the "eye of the oven," which was made to ensure sufficient air circulation, as well as used to clear out the oven from its accumulated wood-ash. This oven had a flat, detachable ceramic lid made for it, with its own distinct rim, and which lid covering could be placed on its top and could hold additional pots and pans when needed. In such ovens, flat dough was pressed against the interior wall of the oven, whereunto it adhered until it was baked. Unleavened bread at Passover was made in the same way. The sealed pot containing the Yemenite-Jewish kubaneh was also placed in such ovens, laid upon the oven floor, upon its dying embers. Pots containing viands and kettles of coffee were first brought to a boil and then kept hot by brushing aside the coals and embers to one side of the oven, covering the coals over with ashes, and placing the pots and kettles beside the ash-covered coals. Such ovens were almost always built within baking rooms (Arabic: al-daymeh = الديمة) or rustic kitchens adjoining a courtyard.

The tannour described by Dalman in Palestine stood approximately 70 centimetres (28 in) to 100 centimetres (39 in) high, was cylindrical and made of clay. It measured 60 centimetres (24 in) to 70 centimetres (28 in) wide on the bottom and narrowed upwards. From the varied ovens described by him, an earthen oven may or may not be buried in the ground; it can be cylindrical, egg-shaped, pointed or curved. If necessary, it was also possible to convert a large water jug into a tannour. The Tandoor, more commonly called as such in India, Pakistan and in Azerbaijan, is related to the tannour, linguistically.^{[citation needed]}

In cylindrical clay ovens used in Syria Palaestina in the 1st and 2nd centuries CE, and where the opening was on top, they were often equipped with a flat, detachable lid (tablet) made of clay and which was usually perforated to allow for the retention of heat when needed, and the smoke to be emitted.

In some societies, such as in the villages around Aleppo, in Syria, the earthen oven (tannour) was vaulted and egg-shaped, the opening of which was made in the front, and the entire structure built above-ground by having it propped-up upon an earth and stone base. Its outer shell was thick, and could be anywhere between a handbreadth (9 centimetres (3.5 in)) to 15.25 centimetres (6.00 in) in thickness. Such shapes were typically found in Europe and in the British isles. In Europe and Britain, however, bread was baked on the floor of the oven, usually made of brick or tile. The dome-shaped oven in western societies was often built upon a stone and earth plinth to make it higher and easier to use, without having to bend over. Some ovens were made with flues; others without.^{[citation needed]}