By the end of this section, you should be able to understand the different types of literature available and explore the resources available to the O&P practitioner in the search for information; understand the differences in content and quality among the various resources; and to select those resources best suited to answering your question. Although there are a wide range of sources for information, this module specifically focuses on printed information. These materials range from advertisements to peer-reviewed journals and their uses may be for clinical care, education or research. They differ by format, purpose, content, intended audience(s), dissemination and quality. A printed material hierarchy is defined based on content, readership, indexing, and review process.