The document discusses using chat in language teaching. It outlines several reasons for using chat, including connecting classes in different locations and allowing students to practice English outside of class. It describes different types of chat like text, voice, public, and private chat. It also lists popular chat apps like WhatsApp, Google Meet, and Skype. The document provides considerations for using chat effectively and sample chat lesson plans, including introducing the software, setting clear tasks, and having contingency plans. Overall, the document presents chat as a tool to improve English skills and manage large classes.