# Redis as a Message Broker — Redis

Source: https://www.geekswithgeeks.com/en/redis/redis-message-broker

> Pub/Sub vs Streams, and where Redis fits among message brokers.

## Pub/Sub is fire-and-forget

Plain Pub/Sub delivers messages only to subscribers connected **right now** — nothing is stored, so an offline consumer misses it forever. **Redis Streams** (`XADD`/`XREAD`) add a durable, replayable log for when messages must not be lost.

## Not a Kafka replacement

For lightweight, low-latency messaging Redis is excellent; for massive, guaranteed-durable, multi-day event streams, a dedicated broker like Kafka or RabbitMQ is usually a better fit.

**Quiz:** Does plain Redis Pub/Sub store messages for subscribers who are offline?

- [ ] Yes, forever
- [x] No — only currently connected subscribers get it
- [ ] Yes, but only for 24 hours

*Answer:* No — only currently connected subscribers get it. Pub/Sub has no storage — use Redis Streams when messages need to survive for offline consumers.