What is Apache Kafka?

An Introduction to Distributed Event Streaming and Publish-Subscribe Messaging

Fact-Checked & Reviewed by: Hambirrao P | Updated: June 2026 | Verified Technical Expert

Key Takeaways

  • Uses a distributed commit log architecture for high-throughput, fault-tolerant messaging.
  • Enables pub-sub real-time event streaming between source applications and target systems.
  • Handles millions of events per second, making it ideal for microservices and tracking logs.

Introduction to Apache Kafka

Apache Kafka is a distributed event streaming platform used by thousands of companies for high-performance data pipelines, streaming analytics, and integration of system logs. Developed by LinkedIn and later open-sourced, Kafka behaves like a highly reliable distributed messaging queue that stores stream records in a fault-tolerant log.

How Kafka's Pub-Sub Architecture Works

Kafka operates on a publish-subscribe model. Producers publish data events to specific categories called 'Topics'. Consumers subscribe to these topics to read and process the events. Because topics are partitioned across cluster nodes, Kafka guarantees message ordering and allows horizontal scaling to accommodate massive traffic loads.

Why Real-Time Streaming Matters

In modern data engineering, batch processing is often insufficient. Companies need to react to user clicks, transactions, and server logs instantly. Kafka bridges this gap by acting as a high-speed buffer, storing stream records safely while feeding them directly into analytics engines like Spark or real-world operational dashboards.

Kafka CLI Commands for Partition & Message Ingestion

# Start the Kafka event broker daemon
bin/kafka-server-start.sh config/server.properties

# Create a multi-partition topic for IoT clickstream events
bin/kafka-topics.sh --create --topic clickstream-events \
    --partitions 3 --replication-factor 1 --bootstrap-server localhost:9092

# Listen to the event stream in real-time from console consumer
bin/kafka-console-consumer.sh --topic clickstream-events \
    --from-beginning --bootstrap-server localhost:9092

Official Documentation

Access official code repositories and developer documentation.

Official Apache Kafka Documentation ↗

Frequently Asked Questions

When does the next 1-to-1 training intake start?

+

Intakes start twice monthly on the 1st and 15th. The next upcoming 1-to-1 intake starts on October 1, 2026 (with secondary intake on October 15, 2026).

Is Kafka a database?

+

While Kafka stores records on disk in a structured log, it is not a relational database. It is optimized for continuous ingestion and real-time streaming rather than complex query-based lookups.

What is a Kafka topic partition?

+

A partition is a unit of parallelism in Kafka. It divides a topic's log across multiple nodes, allowing multiple consumers to read the data simultaneously and increase system throughput.

Explore Our Career Roles, Roadmaps, & Industry Use Cases

Career Profiles

Career Roadmaps

Industry Use Cases & Projects