Types of painting techniques where pigments are mixed with an organic binder. The meaning of the term “tempera” kept changing over time. It originates from the word temperare, meaning “to mix”, which used to denote a more or less liquid substance used to bind pigments. In the Middle Ages, the term narrowed to mean a binder used to impregnate dry pigments and fix them to the painting base. Later still, the meaning of the term was reduced to water-soluble substances such as eggs, animal glue, and gum arabic. In its narrowest sense, the term denotes a binder based on egg yolk. To this day, experts still disagree about the term’s implications. Thus, some experts consider the term “tempera” to mean any technique requiring the pigments to be mixed with an organic binder. Others distinguish between water-soluble and fatty binders and call the former tempera and the latter oil painting. Meanwhile, the third group of experts use the term “tempera” exclusively for the techniques that use emulsions as binders while separating the other organic binder techniques into animal glue and casein painting; oil, resin, and wax painting; and mixed or combined techniques.