# Everyone confuses these two.

> One is a doorbell. The other is a tape you can rewind.

- **Format:** short video, 10 steps, ~32 seconds
- **Topic:** Event Grid or Event Hubs — the mechanism difference behind two Azure services people confuse because both say "event".
- **Author:** Suthahar Jegatheesan (MSDEVBUILD)
- **Category:** Azure · Azure
- **Tags:** azure, azureeventgrid, azureeventhubs, eventgrid, eventhubs, eventdrivenarchitecture, systemdesign, microsoftazure, azurecloud, cloudarchitecture, dataengineering, az305, msdevbuild
- **Canonical URL:** https://blog.msdevbuild.com/shorts/azure-event-grid-vs-event-hubs/

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## What you'll learn

- The doorbell-or-tape question that settles which one you need
- Push with retries versus pull with offsets and retention
- Why a real pipeline usually ends up using both

## Understand it one step at a time

### 1. Both say event. Not the same

Same word, two completely different jobs — and picking wrong shows up months later, not on day one.

### 2. A doorbell and a tape

A doorbell rings each person once and its job is over. A tape keeps what was recorded and can be rewound.

### 3. One thing, or a stream?

“Order placed” matters on its own. “Driver moved” only means something as part of a series.

### 4. Push, or pull?

Grid calls your handler and expects a 200. Hubs sits there while you read at whatever pace you manage.

### 5. Does anyone read it twice?

A Grid event is delivered and gone. A Hubs event stays in the retention window for anyone who asks.

### 6. Who retries — them or you?

Grid retries a failed delivery with backoff and can dead-letter it. Hubs never retries anything.

### 7. How many per second?

Discrete business events arrive in the hundreds. Telemetry arrives in the millions, in batches.

### 8. Usually you need both

Capture writes a file, that write raises a BlobCreated event, and a Function reacts to it. One pipeline.

### 9. The whole difference in one frame

Five rows. Save this one — it is the answer interviewers are listening for.

### 10. Doorbell, or tape?

Ask that one question and you will never mix these two up again — in a design or in an interview.

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## The takeaway

**One announces. The other remembers.**

If somebody might need it again, you needed the log, not the doorbell.