The video tutorial introduces the concept of windowing in Kafka Streams API, focusing on time-based windowing. It presents a problem of counting invoices in a 5-minute window for each store and provides a solution using windowed aggregation. The tutorial includes a detailed implementation guide with code, explaining the use of a timestamp extractor and event time semantics. It also covers running the application using Docker and explains the concept of tumbling windows, highlighting their fixed size and non-overlapping nature.

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