Time series variables (e.g., presidential approval, public mood liberalism, GDP, inflation, education level) are extremely common in the social sciences. However, due to certain properties, these series cannot always be handled using standard regression approaches. This course serves as an introduction to the world of time series analysis. In this module, we will discuss the essentials of time series with a focus on preparing you for cross-sectional time series analysis.  We will explore the properties of time series (e.g., non-independence of observations, moving averages, unit-roots), and introduce strategies to test and model these data.