ROSAT results on hot and cool stars

I will present selected highlights from ROSAT observations of stellar X‐ray emission. Specifically I will discuss the dearth of X‐ray emission among white dwarfs and new evidence for the occurrence of X‐ray emitting shocks in the winds of early‐type stars. Last I will focus on ROSAT observations of the eclipsing cool star binary systems AR Lac, Algol, YY Gem and α CrB and the resulting implications for coronal structure on these stars.