This document provides an overview of Wikipedia, including its purpose and strengths/limitations as an information source. Key points: - Wikipedia is a free, online encyclopedia written collaboratively by volunteers and available in many languages. It has over 25 million articles. - Strengths include up-to-date coverage, self-correction of errors, and breadth of topics. However, reliability is a concern due to its open editing structure. - The document provides tips on evaluating Wikipedia articles by examining discussion tabs, edit histories, references, and article quality. The "best" articles are featured or marked as good.