> ## Documentation Index
> Fetch the complete documentation index at: https://docs.revreply.com/llms.txt
> Use this file to discover all available pages before exploring further.

# API vs. Webhooks

> Understand the basic differences between APIs and webhooks and when to use each.

# API vs. Webhooks

APIs and webhooks are two common ways for applications to communicate with each other. The main difference is **who initiates the communication**.

An **API** is typically used when your application needs to request information or perform an action.

A **webhook** is typically used when another system needs to notify your application that something has happened.

## APIs

An **API (Application Programming Interface)** allows your application to communicate with another application by sending requests to specific endpoints.

With an API, your application is the one that initiates the request.

For example, your application might send a request to retrieve the latest threads:

```http theme={null}
GET https://api.revreply.com/v1/threads/latest
```

The API processes the request and sends a response back to your application.

### Typical API flow

```text theme={null}
Your application
      |
      |  Request
      v
     API
      |
      |  Response
      v
Your application
```

APIs are useful when you need to:

* Retrieve data.
* Create, update, or delete data.
* Trigger an action.
* Control when a request is made.

## Webhooks

A **webhook** is a mechanism that allows one application to automatically send information to another application when a specific event occurs.

With a webhook, the receiving application does not need to repeatedly ask whether something has changed. Instead, the system that owns the event sends a request to a URL that you provide.

For example, when a new event occurs, RevReply could send a request to your webhook URL:

```http theme={null}
POST https://your-app.example.com/webhooks/revreply
```

The request can contain information about the event that occurred.

### Typical webhook flow

```text theme={null}
RevReply
   |
   |  Event occurs
   v
Webhook URL
   |
   |  Event data
   v
Your application
```

Webhooks are useful when you need to:

* Receive notifications about events.
* React to changes in real time.
* Avoid repeatedly polling an API for updates.
* Trigger automated workflows when something happens.

## Key differences

|                                | API                                        | Webhook                         |
| ------------------------------ | ------------------------------------------ | ------------------------------- |
| **Who initiates the request?** | Your application                           | The system generating the event |
| **When is the request made?**  | When your application asks for it          | When an event occurs            |
| **Communication pattern**      | Request → response                         | Event → notification            |
| **Typical HTTP method**        | `GET`, `POST`, `PUT`, `PATCH`, or `DELETE` | Usually `POST`                  |
| **Common use case**            | Retrieve or modify data                    | Receive event notifications     |
| **Timing**                     | On demand                                  | Event-driven                    |

## API or webhook?

The choice depends on what your application needs to do.

Use an **API** when your application needs to actively request data or perform an action. For example, use an API when you want to retrieve the latest threads at a specific point in time.

Use a **webhook** when your application needs to be notified automatically when something happens. For example, use a webhook when you want your application to react as soon as a new event is available.

In many integrations, APIs and webhooks are used **together**. A webhook can notify your application that an event occurred, and your application can then use an API to retrieve additional information or perform a follow-up action.

## Simple example

Consider an application that needs to keep track of new threads.

With an **API**, your application could periodically ask:

```text theme={null}
"Are there any new threads?"
```

With a **webhook**, the system could notify your application:

```text theme={null}
"A new thread is available."
```

Your application could then use the API to retrieve the thread details.

This combination allows webhooks to provide timely notifications while APIs provide a way to retrieve or manipulate the underlying data.