Color sensing is a unique ability of human beings, and has been the basis of many art works and sensor development. This seminar course will cover the origin of color and fluorescence, and their application in sensor and probe development for bioimaging. Through the teaching and learning of basic concepts, students will prepare presentation material with given key words and case studies after they have achieved a deeper understanding of the topic. Every class will end with a small quiz to measure the level of understanding of the topic by the students. The Q&A in the quiz will be used for clarifying any misconception in the next class.