Probability theory studies relations between random quantities. As you have seen, these relations depend on our assumptions: what is random, exactly how is it random, how are multiple random variables defined on the same space, and so on.
This chapter pulls together several observations about the dependence between random quantities. Some of the observations have been made earlier in scattered examples. The aim of this chapter is to develop an organized way in which to approach calculations involving dependence. The chapter ends with a new distribution that is a close relative of the binomial but applies to random samples drawn without replacement.