This document provides an introduction to blended learning. It defines blended learning as integrating classroom face-to-face learning with online learning. Various blended learning models are described, including the flipped classroom and station rotation models. The document outlines a backwards design strategy for developing blended courses, including identifying learning objectives, determining assessments, and planning learning activities. Best practices for blended course delivery such as interactive learning and video lectures are also discussed. Resources for developing blended courses are provided.