An encyclopedia is a comprehensive reference work that provides information on a wide range of topics. It is typically organized alphabetically and includes articles that summarize knowledge in various fields, such as science, history, art, and technology. Encyclopedias can be found in print or digital formats, making them accessible to a broad audience. The purpose of an encyclopedia is to educate and inform readers by presenting facts and summaries in a clear and concise manner. Many encyclopedias are collaborative efforts, with contributions from experts in different areas, ensuring that the information is accurate and reliable. Popular examples include Encyclopedia Britannica and Wikipedia.