Elastic machine learning offers valuable tools for detecting unusual patterns in large datasets by employing rare analysis techniques, which are particularly beneficial in identifying security threats, unauthorized access, or potential issues within time series data. The rare function, a key component of Elastic's anomaly detection, helps identify infrequent occurrences by analyzing frequency over time or within a population, making it distinct from outlier detection, which focuses on distance and density metrics. Rare analysis can be applied in various contexts, such as detecting unusual user activity or new error occurrences in applications, and is especially useful in security threat hunting by highlighting anomalies in login frequencies or unexpected process executions. The effectiveness of rare analysis relies heavily on the chosen bucket span for aggregating data, influencing the sensitivity of the detector to frequency changes. Additionally, the severity scoring system in Elastic's anomaly detection provides insights into the rarity of detected anomalies, aiding security practitioners in evaluating potential risks. Elastic machine learning's rare function is a crucial tool for identifying unique signals in data, with further resources available for users via Elastic Cloud trials and future posts on specific use cases.