Teacher unions are hard to miss in the news lately. Newspapers, blogs, social media posts, magazine articles, and political speeches abound with talk of them. Teacher unions are a hot topic and one that probably was not covered in college classes. The noisy back-and-forth among partisans can be both mind-numbing and confusing, often creating a good deal of heat and shedding very little light on an important topic. A little information, however, can help clarify things and provide a foundation on which teachers can make informed judgments and decisions. This article offers a brief primer on teacher union The author discusses why unions were originally formed, what collective bargaining is, and what's covered in a contract.