This document discusses Uber's use of big data and real-world examples. It describes how Uber handles millions of daily rides and billions of recorded rides globally. It discusses how Uber uses Kafka to centrally handle data from different sources and formats at varying throughput. It also discusses how Uber uses Cassandra for its noSQL database needs like reading user and driver location data with fast response times. It provides examples of how Spark can be used to do real-time and batch processing on Uber's huge volumes of data to gain insights. Finally, it proposes a hypothetical system called Cablito that could be built to handle Uber's personal user data, process booking requests and rides data, and perform analytics on metrics and historical data.