"Tempera" can refer to any water based paining media. Plant gums, glues, egg yolk, egg white glair are
all "temperas". The term derives from the Old English "temprian"; to bring something into required condition
by mixing it with something else.
Egg Tempera is a specific tempera paint made with egg yolk as the binder. Yolk is a natural emulsion of oil and
water. Egg tempera paint dries first by evaporation of the water and then by the "drying" of the oil. The resulting
painting has a soft sheen from the egg oil coupled a crisp linear quality typical of water thinned media.
While associated with the structured, systematic techniques of Byzantine Icon painters and the Italian
Masters of the Trecento egg tempera can be used freely and spontaneously if desired. It should not however be
applied in thick imopsoto brush work. It dries very quickly and should be built up in multiple layers.