All real industrial and living systems involve the transport of matter (mass, volume, species…) and of energy (heat, electric charge, kinetic energy, momentum…) with or without the presence of chemical or biochemical reactions. All these systems are out of equilibrium. Classical equilibrium thermodynamics provides information on the limiting behavior of such systems, but not on their dynamics or kinetics. The usual engineering description of transport phenomena is often limited to a single entity, mass or heat or momentum or electric charge, and provides no general and consistent framework when such phenomena occur simultaneously and are coupled, a fortiori in the presence of chemical reactions. Non-Equilibrium Thermodynamics (NET), also designated as Thermodynamics of Irreversible Processes (TIP), fills this gap. It, thus, addresses the domains usually covered by engineers but in a generalized fashion and with somewhat different tools which complete and enrich the engineering approach.