Visual Rhetoric is a fairly recent theoretical development explaining how images communicate meaning to the audience. It is considered a component of visual literacy (two other components being visual thinking and visual learning).
Using Visual Rhetoric helps to make a text or presentation more efficient. It includes the use of images, charts, illustrations, colors, the arrangement of elements within a text, the choice of fonts etc.
In the academic field, the study of Visual Rhetoric is intended to fill the gap in Traditional Rhetoric, which previously had a tendency of ignoring visual elements, considering them unimportant. The study of Visual Rhetoric is closely linked to Semiotics, a science studying signs and their meaning.
The same image may mean different things to people from different cultures or societies. To convey the exact message and get the desired effect, the author must carefully choose his/her audience.
As the contemporary society becomes increasingly visual, knowing and understanding Visual Rhetoric becomes more significant.
Even if a text is plain and has no illustrations, it still provides a certain visual image to its readers.