This book offers an elementary, self-contained approach to the
mathematical theory of viscous, incompressible fluid in a domain of the
Euclidian space, described by the equations of Navier-Stokes. It is the
first to provide a systematic treatment of the subject. It is designed
for students familiar with basic tools in Hilbert and Banach spaces, but
fundamental properties of, for example, Sobolev spaces, are collected in
the first two chapters.