This document discusses personal learning networks (PLNs) and how educators can develop their own PLNs. It defines a PLN as a network of people and resources that contribute to a learner's professional development. PLNs allow learners to connect, collaborate and contribute without having to know people personally. The document then provides examples of websites and social media platforms educators can use to expand their PLNs, including Twitter, NINGs, Classroom 2.0, Discovery Education, and PBS Teacher. It encourages readers to sign up for accounts and find groups with similar interests to develop their PLN.