There are many kinds of ceramics. They include pottery, wall tiles, bricks and cement. For pottery, wall tiles and bricks, the clay is heated to make useful objects.
Clay is made from very tiny particles. When the clay particles get very hot they begin to change into a natural glass. The edges of the clay melt into glass first, and then, if the temperature is lowered, the glass sets, holding the particles together.
There are many other processes that can be added to make all the different kinds of ceramics. Some have rough, brown surfaces while others have smooth, shiny, brightly-coloured surfaces.
The main ceramics are greenware (unfired), earthenware (short firing, low temperature), stoneware and porcelain (highest temperature, longest firing, finest -kaolin- clay).
These are all detailed in the pottery book below.