Can you explain what is meant by a topic in Kafka system?

In Apache Kafka, a topic is a logical category or channel where messages are published. A topic is a sequence of records (messages) that are ordered and stored for some time. Producers send messages to a topic, and consumers read from it. Topics are divided into partitions, which allow scaling processing and provide parallelism. Each message in a partition has a unique offset, which consumers use to track their position.

Interaction:

1. When creating an image, Docker sequentially applies instructions from the Dockerfile, creating a new layer for each instruction that modifies the filesystem.
2. Layers are cached and can be reused to speed up build times.
3. When a container runs, Docker combines all layers into a single virtual filesystem.

This approach allows efficient disk space usage and faster deployment and updates of containers.