This document provides an introduction to statistics. It defines statistics as the science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making more effective decisions. There are two main types of statistics: descriptive statistics, which summarize and organize data; and inferential statistics, which are used to estimate properties of populations based on samples. Variables can be qualitative or quantitative, and quantitative variables can be discrete or continuous. There are four levels of measurement for variables: nominal, ordinal, interval, and ratio. Ethics are also important in the practice of statistics.