What’s the most prominent in Yoon’s work at first sight is the ‘color’. The nearly raw, vibrant colors have become the artist’s trademark. In addition, his own way of applying bold colors as well as the deliberate combination of diverting facial expressions and different props are well cheered by his supporters. Each color contains its own look and emotion. A color holds the capacity to affect human physiology or emotion. In other words, humans see colors not only with their eyes, but also with their hearts. Therefore, the colors we see induce our everyday experiences or the environment that directly affect our body and emotion. The stimulating colors in Yoon’s work represent each character’s various experiences and complex emotions from the unconsciousness. The viewer may be seized with the net of colors woven by the artist, and will acknowledge each character’s personality just as prescribed on the canvas. Yoon’s colors retain a curious energy that appeals to the public's psychological states. This explains why he is praised as one of the greatest Korean Pop-artists. While the extravagant but harmonizing use of primary colors determines the visual formality of Yoon’s work, the characters with different facial expressions become the messengers that convey his central theme. His message centers on 'friends', his closest acquaintances who share deep rapport with him. They often appear as heroes or as their ordinary selves, and the small items they carry with suggest their personalities.