In painting and visual arts, "tone" refers to the lightness or darkness of a colour. It is determined by how much white or black is mixed with a colour:
Tone is crucial in creating depth, contrast, and mood in a painting. In the context of painting and decorating (as a tradesman or contractor), understanding tone helps in colour matching, creating harmonious colour schemes, and ensuring the desired visual effect in a space—whether it's making a room feel brighter, more spacious, or more intimate.
In summary:
Tone = how light or dark a colour appears.