This document provides an overview of communication, including defining communication, outlining the communication process, describing types and levels of communication, and discussing barriers to effective communication. Communication is defined as the exchange of information, ideas, thoughts, feelings, and emotions through speech, signals, writing, and behavior. The key aspects of the communication process are the sender, message, encoding, media, decoding, receiver, feedback, and potential noise. Types of communication include verbal (oral and written) and nonverbal. Levels of communication range from intrapersonal to interpersonal, small group, one-to-group, and mass communication. Potential barriers to effective communication discussed are physical, cultural, language, emotional, gender, organizational,