All things are surrounded by principles. Art too has principles. Abiding with these principles, a great work of art is achieved.
When the different elements of art are organized, it is then called the principles of art. The elements of art include the light, texture, form, color, space, mass and line. To put these elements into the principles of art, we unite the elements, balance, emphasize and contrast them. We also make a lot of variations, patterns and movement of these elements.
Emphasis. Basically, it makes something stands out above all others, in music, design, drama, painting and so on. In a movie, like for an example, if you want to emphasize the scene when the main characters won a victory, then make it more catching above all other scenes. It is like you want to make that scene the most important scene that everyone should watch.
Contrast has to do with opposites. The bigger the difference between two things, the higher the contrast. It could be opposites in color, environment, shape, length, shadow and so on.
Variety. To make differences in any artworks. It can be differences in sizes, patterns and colors. In music, in concert, you will not only see colorful stages, lead singer but also back-up dancers and even surprise guests.
Unity. It refers to the quality of wholeness and oneness. It is created through calmness, simplicity and repitition. Putting all cool colors together, linking all kinds of shapes, or it could be mixture of light and drak texture.
Pattern. It can be predictable or mechanical pattern. Regular repeated element of art. It should be consistent so that the pattern can be distinguished.
Balance. Symmetry and assymetry do matter in this principle. It could be the same stuff of each side creating balance. It would be the weight that is evenly distributed throughout the image.
Movement. How to project a man running, a water flowing? It is through the principle of movement.