Kafka in 100 Seconds

Apache Kafka, created in 2011 at LinkedIn, is a system optimized for writing real-time data. It uses a producer API to create records stored in an immutable log called a topic. Topics are distributed across a cluster of brokers, making Kafka fault-tolerant and scalable. Consumers can subscribe to topics, reading messages in real-time. Kafka's Streams API allows for data transformation and aggregation. It is used by companies like Lyft, Spotify, and Netflix for various data processing tasks. Setting up Kafka involves tools like Zookeeper, and it supports advanced streaming capabilities.

Describe the difference between stateless and stateful transformations in Kafka Streams API.

List some companies that use Kafka and their use cases as mentioned in the text.