**What is Pub/Sub?**\
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**Pub/Sub** (Publisher/Subscriber) is a messaging service in Google Cloud that enables asynchronous communication between applications. It allows publishers to send messages to a topic, while subscribers receive messages from that topic. This decouples the systems, so publishers and subscribers can operate independently, making it easier to build scalable and flexible applications. Pub/Sub is commonly used for event-driven architectures, real-time analytics, and stream processing.