The Redis Stack's introduction of t-digest, a new probabilistic data structure, offers an efficient way to estimate percentiles in large datasets. T-digest can be used to answer common questions about data streams and large datasets, including estimating the 50th, 90th, and 99th percentile. The data structure provides sub-millisecond latency, sub-linear memory requirements, and high accuracy, making it suitable for streaming data and huge datasets. With t-digest, users can query statistics such as percentiles, ranks, and trimmed means, allowing them to efficiently analyze and process large amounts of data. Additionally, the Redis Stack's support for t-digest extends its existing functionality, including RedisInsight, search and query, JSON, time series, and probabilistic data structures.