  This Colloquium is a fast journey through the build-up of key thermodynamical
concepts, i.e. work, heat and irreversibility -- and how they relate to
information. Born at the time of industrial revolution to optimize the
exploitation of thermal resources, these concepts have been adapted to small
systems where thermal fluctuations are predominant. Extending the framework to
quantum fluctuations is a great challenge of quantum thermodynamics, that opens
exciting research lines e.g. measurement fueled engines or thermodynamics of
driven-dissipative systems. On a more applied side, it provides the tools to
optimize the energetic consumption of future quantum computers.
