During the last thirty years astronomers have discovered that nearly all stars are losing mass in the form of stellar winds through a major fraction of their lives. This mass loss affects their evolution from their origin to their death. It also leads to spectacular interactions between the supersonic stellar winds and the interstellar medium in the form of planetary nebulae and ring nebulae and in the form of interstellar bubbles and superbubbles. The return of matter from stars into the interstellar medium and the formation of bubbles and superbubbles changes the chemical composition of the galaxies and affects their kinematical properties.
Literature in this field has grown tremendously over the past three decades. On the one hand this is due to the advance of spectroscopic observations over the full range of the spectrum and to the enormous improvements in image resolution from ground based telescopes and the Hubble Space Telescope which results in spectacular images of the nebulae formed by stellar winds. On the other hand it is the result of many theoretical studies to explain the basic mechanisms for stellar winds and the interactions with their surroundings. Many reviews have been published that give an overview of specific aspects of stellar winds or mass loss from stars.