  The majority of all stars are members of a binary system. The evolution of
such binary stars and their subsequent production of pairs of compact objects
in tight orbits, such as double neutron stars and double black holes, play a
central role in modern astrophysics, Binary evolution leads to the formation of
different types of violent cosmic events such as novae, supernova explosions,
gamma-ray bursts, mass transfer and accretion processes in X-ray binaries, and
the formation of exotic radio millisecond pulsars. In some cases, the binary
systems terminate as spectacular collisions between neutron stars and/or black
holes. These collisions lead to powerful emission of gravitational waves, as
detected by LIGO since 2015. The coming decade is expected to reveal a large
number of discoveries of binary compact systems, as well as their progenitors
and merger remnants, from major instruments such as the radio Square-Kilometre
Array; the gravitational wave observatories LIGO-Virgo-KAGRA-IndIGO and LISA;
the astrometric space observatory Gaia; the James Webb Space Telescope; and the
X-ray space observatories eXTP, STROBE-X, and Athena. In this light, it is
important to have a modern textbook on the physics of binary stars evolution,
from ordinary stars to X-ray binaries and gravitational wave sources. The scope
of this book is that the reader (student or educated expert) will learn the
physics of binary interactions, from stellar birth to compact objects, and
relate this knowledge to the latest observations. The reader will learn about
stellar structure and evolution, and detailed binary interactions covering a
broad range of phenomena, including mass transfer and orbital evolution,
formation and accretion onto compact objects (white dwarfs, neutron stars and
black holes), and their observational properties. Exercises are provided
throughout the book.
