Elasticsearch provides insights into its operations through logging, which can help identify errors, performance issues, or undesirable cluster behaviors. Main logs are stored in a default INFO level file, while slowlogs reveal the speed of queries and other operations. Log levels can be dynamically adjusted without restarting nodes, allowing for detailed monitoring of specific Java packages or sections within Elasticsearch. This flexibility extends to slowlogs, allowing index-level logging adjustments to focus on specific indices without affecting others. Groovy scripts can include logging to debug and verify script functionality, and with the advent of Elasticsearch 2.0, a deprecation log was introduced to inform users of deprecated settings and features.