The phrase warm color is used to describe any color that is vivid or bold in nature. Warm colors are those that tend to advance in space and can be overwhelming. Examples of warm colors include red, yellow and orange (think exciting fire and volcanoes).
In page layout, illustration and sculpture, white space is often referred to as negative space. It is the portion of a page left unmarked: margins, gutters, and space between columns, lines of type, graphics, figures, or objects drawn or depicted, and is not necessarily actually white if the background is of a different color. The term arises from graphic design practice, where printing processes generally use white paper. White space may be an element of design rather than just space left blank. source