Azure Event Hubs
Azure Event Hubs is a highly scalable managed service capable of ingesting millions of events per second, enabling you to capture, process, and analyze massive amounts of data originating from connected devices (often IoT scenarios) and applications. You can think of Event Hubs as a gateway, or entry point, for an event processing pipeline. Data is collected into an Event Hub, then transformed and stored. You have control over what data transformations and storage are needed.
The programmatic interface for Event Hubs is AMQP (Advanced Message Queuing Protocol) or HTTP(S), making it very easy for a wide range of clients to publish event data to Event Hubs. To support the need for massive scale, Event Hubs uses a partitioning pattern to scale the load internally. Receiving messages from an Event Hub is handled via consumer groups. Consumer groups are responsible for knowing from which partition to read and maintaining a view (state, position in the stream, etc.) of the Event Hub.
You will often see Azure Event Hubs used to ingest data in a big data or IoT scenario. A characteristic of both scenarios is the generation and processing of large volumes of (often relatively small in size) data. To process and analyze the data, another Azure service, Azure Stream Analytics, is often paired with Event Hubs.
It is important not to confuse Event Hubs with Azure Service Bus queues or topics. While the two are similar in that they are both messaging systems, Event Hubs is designed specifically for handling message events at high scale. It does not implement some of the messaging capabilities of Service Bus queues and topics, such as dead lettering, filters (property based routing), and various message retrieval, delivery, and scale semantics. Service Bus is better suited for per-message needs, while Event Hubs is better suited for event streaming needs.
Source of Information : Microsoft Azure Essentials Fundamentals of Azure Second Edition