Quantum information theory studies general laws of information storage and transmission in the systems obeying quantum mechanics, by using mathematical models of information processors -- communication channels -- for investigation of potential capabilities of such systems and elaborating the principles of their rational and reliable design.

The notion of channel capacity is central in the classical information theory. It turns out that in the quantum case this notion splits into the whole spectrum of information characteristics of a quantum channel. This paper presents a survey of the main concepts and results, gives formulation of the «coding theorems» providing analytical expressions for the capacities of quantum communication channels on terms of entropic quantities, stressing the special role played by the quantum property of entanglement.