This paper is a tutorial review of the structure, composition, and statistical modeling of the organization of the neocortex. It begins with a general overview of the layered structure of the neocortex and its organization as a network of interconnected functional columns. Next it discusses the various classes of neurons that populate the neocortex using as a classification system the several generic types of signals produced by cortical neurons. This is followed by a discussion of characteristics in neuron-to-neuron signaling. Finally, it reviews some of the general trends found in the cortical organization.