  These are lecture notes for a series of lectures given at the Les Houches
Summer School on Integrability in Atomic and Condensed Matter Physics, 30 July
to 24 August 2018. The same series of lectures has also been given at the Tokyo
Institute of Technology, October 2019. I overview in a pedagogical fashion the
main aspects of the theory of generalised hydrodynamics, a hydrodynamic theory
for quantum and classical many-body integrable systems. Only very basic
knowledge of hydrodynamics and integrable systems is assumed.
