This book focuses on the equation of state (EoS) of compact stars, particularly the intriguing possibility of the "quark star
model." The EoS of compact stars is the subject of ongoing debates among astrophysicists and particle physicists, due to the
non-perturbative property of strong interaction at low energy scales. The book investigates the tidal deformability and maximum
mass of rotating quark stars and triaxially rotating quark stars, and compares them with those of neutron stars to reveal
significant differences. Lastly, by combining the latest observations of GW170817, the book suggests potential ways to distinguish
between the neutron star and quark star models.