Hand computations are the foundation of this book because seeing the numbers and working with the formulas facilitates an understanding of statistical analyses. In the real world, however, statistical analysis is generally conducted using a software program. Microsoft Excel contains some rudimentary statistical functions and is commonly used in situations requiring only basic descriptive analyses; however, this program’s usefulness is exhausted quickly because researchers usually want far more than descriptives. Many statistical packages are available. The most common in criminal justice and criminology research are SPSS, Stata, and SAS. Each of these packages has strengths and weaknesses. Simplicity and ease of use makes SPSS a good place to start for people new to statistical analysis. Stata is a powerful program excellent for regression modeling. The SAS package is the best one for extremely large data sets.