Event Grid and Event-Driven Architecture

In an event-driven architecture, components communicate by publishing and subscribing to events rather than calling each other directly. A component (producer) emits an event when something noteworthy happens — a file is uploaded, an order is placed, a device sends a reading. Other components (subscribers) react to events they care about, independently and asynchronously. This decouples producers from consumers, improving scalability, resilience, and maintainability.

Azure Event Grid is a fully managed event routing service that delivers events from sources (publishers) to handlers (subscribers) using a push model. Event Grid is designed for reactive, discrete events — something changed and you need to react immediately. It guarantees at-least-once delivery with automatic retry, supports filtering so subscribers only receive relevant events, and can route events to Azure Functions, Logic Apps, webhooks, Event Hubs, and Service Bus queues.