What is the meaning of value in Art?

Value / Tone
A very important element in, especially drawings and paintings, is value (or tone). In this context, value means light and dark. Sometimes referred to by the Italian Word "chiaroscuro" (literally "light/dark"), value is often described visually by a scale with varying shades of gray arranged between black and white. But remember that colors have values also-what would you call a light value of red?
Similar values distributed in patterns throughout a work of art can lead the viewer's eyes around the piece to receive the message the artist intended to send. Thus value is an important compositional device, but values can be used to create the illusion of space as well.