The word ceramic is derived from the Greek word κεραμικός (keramikos). The term covers inorganic non-metallic materials which are formed by the action of heat. Up until the 1950s or so, the most important of these were the traditional clays, made into pottery, bricks, tiles and the like, along with cements and glass. Clay-based ceramics are described in the article on pottery. A composite material of ceramic and metal is known as cermet. The word ceramic can be an adjective, and can also be used as a noun to refer to a ceramic material, or a product of ceramic manufacture. Ceramics may also be used as a singular noun referring to the art of making things out of ceramic materials. The technology of manufacturing and usage of ceramic materials is part of the field of ceramic engineering.

Many ceramic materials are hard, porous, and brittle. The study and development of ceramics includes methods to mitigate problems associated with these characteristics, and to accentuate the strengths of the materials as well as to investigate novel applications.

The American Society for Testing and Materials (ASTM) defines a ceramic article as “an article having a glazed or unglazed body of crystalline or partly crystalline structure, or of glass, which body is produced from essentially inorganic, non-metallic substances and either is formed from a molten mass which solidifies on cooling, or is formed and simultaneously or subsequently matured by the action of the heat.”

Types of ceramic materials

For convenience ceramic products are usually divided into four sectors, and these are shown below with some examples:

• Structural, including bricks, pipes, floor and roof tiles
• Refractories, such as kiln linings, gas fire radiants, steel and glass making crucibles
• Whitewares, including tableware, wall tiles, decorative art objects and sanitary ware
• Technical, is also known as Engineering, Advanced, Special, and in Japan, Fine Ceramics. Such items include tiles used in the Space Shuttle program, gas burner nozzles, ballistic protection, nuclear fuel uranium oxide pellets, bio-medical implants, jet engine turbine blades, and missile nose cones. Frequently the raw materials do not include clays.

Examples of whiteware ceramics

• Bone china
• Earthenware, which is often made from clay, quartz and feldspar.
• Porcelain, which are often made from kaolin
• Stoneware

Classification of technical ceramics

Technical ceramics can also be classified into three distinct material categories: