This chapter serves as the foundation of understanding the underlying concepts related to statistics. This chapter should be read over and over and over again, as it is key to understanding the remainder of the book. Such important concepts as sample vs. population, data management, Central Limit Theorem, and when to use parametric vs. non-parametric procedures are introduced. It provides concise descriptions and examples of basic measures of central tendancy (mean, median, mode range, interquartile range, etc.), measures of disperion around the averages, description of continuous vs. non-continuous measures, normal vs. non-normal distributions, log distributions, confidence intervals, and when to use one-sided vs. two-sided P-values. Many example calculations of sample size and power are also described for a number of different test situations.