This book introduces the basic concepts of algebraic topology using homoto-
py-theoretical methods. We believe that this approach allows us to cover
the material more efficiently than the more usual method using homological
algebra. After an introduction to the basic concepts of homotopy theory,
using homotopy groups, quasifibrations, and infinite symmetric products,
we define homology groups. Furthermore, with the same tools, Eilenberg-
Mac Lane spaces are constructed. These, in turn, are used to define the
ordinary cohomology groups. In order to facilitate the computation, cellular
homology and cohomology are defined.