This document provides an introduction to statistics in psychology. It discusses the origin of statistics, noting that the word comes from the Latin word for state. It then covers the history and development of statistics from the 1600s to present day. Key definitions of statistics are presented. The functions of statistics are listed as collection, classification, condensation, comparison, correlation, and causation. Descriptive and inferential statistics are introduced as the two main branches. Limitations and types of statistics are also briefly outlined.