Contents -- Preface -- Chapter 1 Historical introduction -- Chapter 2 The deflection of light -- 2.1 Basics of General Relativity -- 2.1.1 Introduction -- 2.1.2 Tensors in curved spacetimes -- 2.1.3 Motion of particles -- 2.1.4 The spacetime curvature -- 2.1.5 The Einstein equation -- 2.1.6 The Schwarzschild metric -- 2.2 The bending of light -- 2.2.1 Point-like deflector -- 2.2.2 Time delay -- 2.2.3 Extended mass distribution -- Chapter 3 Gravitational lensing theory -- 3.1 The lens equation -- 3.1.1 Point-like lenses -- 3.1.2 Extended lenses -- 3.2 The surface brightness conservation -- 3.3 Amplification -- 3.4 Caustics and critical lines -- 3.5 Fermat's principle -- 3.6 Galaxy lens models -- 3.6.1 Circularly symmetric lenses -- 3.6.2 Non-circularly symmetric lenses -- 3.7 The folded sky -- 3.8 Folds and cusps -- 3.8.1 Magnification near a fold -- 3.8.2 Magnification near a cusp -- 3.8.3 The binary lens -- Chapter 4 Macrolensing results -- 4.1 Lensing of quasars -- 4.2 Time delays and H0 -- 4.3 Statistical lensing and cosmological parameters -- 4.4 Strong lensing by clusters -- 4.5 Weak lensing in clusters -- 4.6 Cosmic shear -- 4.7 Quasar-galaxy correlations -- 4.8 Lensing of the Cosmic Microwave Background -- Chapter 5 Microlensing I: Basics -- 5.1 The Galaxy in brief -- 5.1.1 The thin and thick disks -- 5.1.2 Galactic spheroid and bulge -- 5.1.3 The dark halo -- 5.2 Basic microlensing theoretical tools -- 5.2.1 The light curve -- 5.2.2 Optical depth -- 5.2.3 Event duration distribution -- 5.3 Microlensing of unresolved sources -- 5.4 Observational searches of microlensing -- 5.4.1 Searches towards the Magellanic Clouds -- 5.4.2 Searches towards the bulge -- Chapter 6 Microlensing II: Beyond the simplest light curve -- 6.1 Binary lenses -- 6.1.1 The complex lens equation -- 6.1.2 Microlensing by binaries.

6.1.3 Planetary searches -- 6.2 Further determinations of the lensing parameters -- 6.2.1 Proper motion -- 6.2.2 Limb darkening -- 6.2.3 Parallax measurements -- 6.3 Astrometric microlensing -- 6.4 Quasar microlensing -- Appendix A Cosmology tools -- A.l The Friedmann-Robertson-Walker Universe -- A.2 The distance scales -- A.3 Large scale structures -- A.4 Cosmic Microwave Background anisotropies -- Bibliography -- Index.