> Markdown version of https://www.asyncapi.com/docs/concepts/producer
> Index: https://www.asyncapi.com/llms.txt

# Producer

## What is a Producer? 
A _producer_ is an application that detects state changes (_events_) and publishes these events as messages. An event signifies a state change or update triggered by a user’s or device’s action.

The following are sample events:
* Adding an item to a shopping cart on an e-commerce website.
* Clicking the subscribe button on a YouTube channel.
* Detecting a temperature change using a sensor.

## Why do we need Producers? 
The publish/subscribe communication model is one of the core concepts of event-driven architecture. In this model, producers are publishers, acting as the first logical layer responsible for distributing messages to the broker, enabling others to subscribe and receive these messages.

```mermaid
flowchart TD
    a[Producer]-- Message 1 --->d[(Broker)]
    d -- Message 1 --->g[Consumer]
```

The diagram above illustrates the communication flow between a producer who publishes events to a specific channel in a broker and a consumer who subscribes to the same channel.

In some cases, an entity can simultaneously function as both a producer, publishing messages to a specific channel in the broker, and a consumer, subscribing to messages from a different channel in the broker.

```mermaid
flowchart LR
    a[Producer]-- Message 1 --->c[(Broker)]
    b[Producer]-- Message 2 --->c
    c -- Message 1 --> b
    c -- Message 2 ---> d[Consumer]
```

In the diagram above, there is a producer publishing messages to a specific channel and a consumer subscribing to messages from that channel. Also, there is a second producer publishing to one channel and subscribing to messages from another channel.