Secondary sources are documents or recordings that analyze, interpret, or summarize information from primary sources. They provide context and commentary on original materials, such as historical documents, interviews, or artifacts. Examples of secondary sources include books, articles, and documentaries that discuss events or topics based on firsthand accounts. These sources are valuable for research because they help to synthesize information and present different perspectives. However, it is important to evaluate their credibility and bias, as they may reflect the author's interpretation rather than the original facts. Understanding secondary sources can enhance comprehension of complex subjects.