Painting

Pastel or pastels is an artistic expression which involves the application of soft colours by painting with soft crayons wrapped in paper. Ideally, this results in a soft and delicate painting, although a modern school involves bolder applications. The procedure and materials sometimes make it difficult for the artist to fix mistakes, but the medium can be a forgiving one under most circumstances.

Pastel crayons or sticks, which resemble chalk, consist of pure pigment combined with an inert binder. They are available in varying degrees of hardness, the softer varieties being wrapped in paper.

The colours are simply drawn onto the artwork surface, usually paper. Some artists protect their finished pieces by spraying them with a fixative. In all cases, the pastel drawing or painting must be framed under glass to further protect it from smudging, environmental hazards, humidity, and so on.

There are also oil pastels.
Pastel colour is a general term for any colour that is softly muted as it would be if drawn with pastels, but used most commonly for lighter-tinted colours such as a muted pink, but not necessarily a muted red or muted navy blue.
Oil painting is done on surfaces with pigment ground into a medium of oil - especially in early modern Europe, linseed oil. Other oils occasionally used include poppy seed oil, walnut oil, and safflower oil. These oils result in different properties in the oil paint, such as less yellowing or different drying times.
It was probably developed for decorative or functional purposes in the High Middle Ages. Surfaces like shields - both those used in tournaments and those hung as decorations - were more durable when painted in oil-based media than when painted in the traditional tempera paints. Many Renaissance sources credit northern European painters of the 15th century with the 'invention' of painting with oil media on wood panel - Jan van Eyck often mentioned as the "inventor".

Recent advances in chemistry have...