This chapter discusses the history of the concept of galaxy; and how it emerged as instrumentation developed and distance-measurement methods merged. A century ago it was established beyond doubt that we live in one among many galaxies. In some ways we know more about our galaxy because of its proximity to us, but in other ways we know less because our view is obscured by cosmic dust. It is easier to see the centers of other galaxies. The chapter gives a brief account of what we know today.