Research would not be possible, at least, partly, without the important methodological contribution made by statistics, and namely, quantitative methods. This book intends to illustrate with numerous examples how quantitative methods may be used for the sake of Second Language (L2) Education research. The scholarly community has seen a growing interest in statistical methods for L2 research (Plonsky, 2015), but to date, few publications have attempted to provide a comprehensive overview of what the role of statistics is in L2 education research. To do so, this book provides the reader with a steady introduction to statistical methods from basic elements (i.e. descriptive statistics) to more challenging analyses (e.g. linear regression or Bayesian statistics). This book intends to offer a basic, but wide-ranging perspective of Bayesian statistics - a statistical trend acquiring importance in L2 research. Additionally, an overview of effect sizes will be presented (see Plonsky & Oswald, 2014). These statistical methods are presented with examples based on L2 education research, accompanied by explanations on how to perform these analyses using a statistics software package (JASP).