We introduce general-education students to key ideas in applied computing through case studies from computer graphics, computer animation, image processing, computer vision, information retrieval, and artificial intelligence. Each case study consists of two lectures: one an intuitive exposition of relevant computer-science concepts, and the other a hands-on introduction to a working system that embodies these concepts. Students use these systems to perform design and problem-solving tasks, thereby reinforcing the abstract concepts presented. Computer programming is neither required nor taught. The course has been offered for two years at the Harvard University Extension School, and has achieved high ratings in student surveys.