This document discusses personal learning networks (PLNs) for teachers. It defines a PLN as a way for teachers to personalize their own learning. Teachers can use PLNs to gather resources, connect with experts, and stay up-to-date in their field. Five common types of PLNs are discussed: casts (podcasts and videos), social networks, blogs, microblogs (Twitter), and social bookmarking sites. Aggregators are also covered as a way to bring content from various PLN sources together in one place. The document provides many examples of existing PLNs and encourages readers to create their own PLN to facilitate ongoing professional learning and networking.