Wikipedia
Painterwork accomplishes two things, namely the preservation and the coloration of the material which is painted. The compounds used for painting, taking the word as meaning a thin protective and/or decorative coat, are very numerous, including oil paint of many kinds, distemper, whitewash, tar; but the word paint is usually confined to a mixture of oil and pigment, ground together in a process that thoroughly coats every small particle of pigment in oil, together with other materials which possess properties necessary to enable the paint to dry hard and with a degree of flexibility and to varying degrees of opacity/translucency. Oil paints are made up of four parts, the base, the vehicle, the solvent and the driers. Pigment may be added to these to obtain a paint of any desired color. There are several bases for oil paint, those most commonly used for building work being white lead, red lead, zinc white and iron oxide.