This chapter introduces the key concepts of the book and provides context for the experimental work to be reported in later chapters. First, we discuss the importance of unsupervised individual learning in education and the importance of homework. A brief history of homework in American education, from the early 19th century to the present, is presented. The development of homework as a standard part of formal education is reviewed, and the recurring issues in favor of and against homework are discussed. The relationship of unsupervised individual learning to supervised group learning and the relationship of unsupervised individual learning to homework are discussed.