In this article, the importance of indexing in MongoDB is highlighted as a key factor in improving performance. Indexing allows for efficient querying and filtering of data, reducing the need to scan entire collections. The article provides best practices for creating and maintaining effective indexes, including using composite indexes, following the ESR (Entire-Scan-Range) rule, and avoiding unnecessary indices. Additionally, it discusses the use of full-text search, multi-key indexes, and explain plans to optimize queries. The article also emphasizes the importance of monitoring index usage and adjusting accordingly to avoid performance issues. Overall, this article provides a comprehensive guide to indexing in MongoDB for improving performance and reducing database overhead.