Pub/Sub

Pub/Sub is a fully-managed, real-time asynchronous messaging service: it decouples publishers from subscribers for scalable event ingestion and delivery.

This is your zero-ops, highly available messaging backbone. Pub/Sub handles the heavy lifting, providing synchronous, cross-zone message replication for at-least-once delivery at any scale (no partitions needed). Publishers send messages to a Topic; Subscribers receive them via a Subscription (Push or Pull). Latency is typically around 100 milliseconds. Use it to ingest high-volume event streams (e.g., user interactions), distribute data to multiple systems (BigQuery, data lakes), or enable robust communication between microservices.

https://cloud.google.com/pubsub/docs