This book of statistical formulas is primarily intended for statistics for professional studies. The typical user will see only a single statistics course, or maybe two if he decides to go advanced, for his entire life. This is not to say that a beginning student of statistics or mathematics may not also find it useful at the start of their studies, but they should not expect it to be their faithful companion far into the more advanced courses. The main angle for statistical inference in this book of formulas is bayesian, simply because it is the simplest and most logical route to applying probability to the many uncertainties in life, and not the least to professional life. A professional needs a robust, workable probability, and therefore he should choose the bayesian way. Still, heeding the still dominant position of the frequentist school, and that the professional may often have to work teams with others schooled in that tradition, we have also included formulas from frequentist inference, and we have also made sure to choose bayesian formulations that will minimize friction while yet retaining the full power of the bayesian way.