Table of Contents

Acknowledgments.- Introduction.- I Quantum Entanglement.- Entanglement in QFT.- Entanglement entropy in CFT2.- Single interval in CFT2.- II Holography and entanglement.- Holographic entanglement entropy.-Deriving holographic entanglement proposals.- Properties of holographic entanglement entropy.- III Entanglement and quantum dynamics.- Quantum quenches and entanglement.- Entanglement in excited states.- Holographic many body systems.- Entanglement and renormalization.- IV Quantum Gravity.- Prelude: Entanglement builds Geometry.-  Entanglement at large central charge.-  Geometry from entanglement.- AdS/CFT and tensor networks.