Complex sentence: Turbochargers were originally known as turbosuperchargers when all forced induction devices were classified as superchargers; nowadays the term "supercharger" is usually applied to only "mechanically" driven forced induction devices.
Split into simpler sentences: Turbochargers were originally known as turbosuperchargers when all forced induction devices were classified as superchargers. Nowadays the term "supercharger" is usually applied to only "mechanically" driven forced induction devices.