We have many reference resources online and in print. Reference sources are a good place to get an overview of a topic in a few paragraphs or a few pages. Looking up a topic in a reference book is an excellent way to familiarize yourself with the key concepts, terminology, and people associated with the topic. This background is important both for understanding a topic and for searching effectively in online databases for articles and books. In addition, many reference works provide carefully selected bibliographies which may lead you to further reading.