CoachThe material of an object is what the object is made of. A spoon can be made of wood, of metal or of plastic: the spoon is the object, the wood is the material.
Examples
Example 1.3 (One object, three materials)
Three spoons lie side by side. They have the same shape and do the same job, so they are the same kind of object. But one is made of wood, one of metal and one of plastic: three different materials.
Example 1.4 (One material, many objects)
Wood is the material of a pencil, a chair, a door, a toy train and a wooden spoon. Many different objects can be made of the same material.
Example 1.12 (Floating and sinking)
Put a few objects in a basin of water. A wooden block and a plastic bottle cap float. A pebble, a glass marble and a steel nail sink to the bottom. Whether a thing floats or sinks is also a property of its material.