This book is directed at the student undertaking a course in star formation for the first time. This may be in the later years of an undergraduate degree in physics, astrophysics, or physics with astronomy. Alternatively, it may be that the student only meets this subject for the first time during the first years of a masters degree. In either case we have assumed that the student already has a grounding in physics and mathematics, including, for example, Maxwell's equations, quantum mechanics and the laws of thermodynamics. Nevertheless, we find from teaching experience that brief reminders to students of things they learnt in other courses are generally welcomed as helpful. Hence, we remind the reader of some of the important points from other branches of physics where they are relevant.

We assume only a minimal knowledge of astronomy, and we derive the necessary astrophysical equations as we go along. We assume no prior knowledge of the subject of star formation itself and begin from first principles. Throughout the book we attempt to stay on ground that is firmly established, and try to avoid that which is trendy or the latest discovery. Experience has taught us that these matters often become outdated much more quickly than the solid foundations on which the subject is based. In cases where we stray onto less sure footing, we inform the reader that we are doing so.