---
title: "Webhook: what it is and how it differs from an API | attendo"
description: "What a webhook is, how it differs from an API, an example with an online store, incoming and outgoing ones, and the mistake of not keeping a delivery log."
url: "https://attendo.me/en/glossary/webhook"
lang: "en"
---

# Webhook: what it is and how it differs from an API

Also known as: HTTP callback · reverse API

A webhook is an automatic notice that one system sends to another, at a web address, as soon as something happens: a new order, a payment or an approved document.

## Webhook vs. API: who calls whom

- **With an API**, your system asks: “any new orders?” If it asks every five minutes, it either finds out late or asks for nothing most of the time.
- **With a webhook**, the other system tells you: “this order just came in.” The notice arrives right away and only when there is something.

They work together: the webhook says something happened and, if you need more detail, you ask for it through the API.

## An example

Your online store receives an order that includes installation. Its webhook notifies your operations system, which creates the work order and puts it on the technician’s schedule. When the technician closes the job, an outgoing webhook tells the store to mark the order as installed.

## Incoming and outgoing

An **incoming webhook** is the address where your system receives notices from others. An **outgoing** one is the notice your system sends to others when something changes inside it.

## The usual mistake

Not keeping a record of what was sent. If the receiving system is down, the notice is lost and nobody finds out. A well-built webhook keeps a delivery history, lets you resend what failed and protects what it sends.

## In attendo

The [API v4](https://attendo.me/en/modules/api-and-mcp) has outgoing webhooks, with history and resend, and incoming ones, so an outside system can start an [attendo Flows](https://attendo.me/en/modules/flows) workflow. Every call is logged in the workflow history.

- [attendo Flows](https://attendo.me/en/flows)

## Where it is used in attendo

### Modules

- [API v4, webhooks and MCP](https://attendo.me/en/modules/api-and-mcp): Connect whatever is not on the list, with permissions per key
- [Flows and AI-Flows](https://attendo.me/en/modules/flows): Flows, phased processes with approvals, and AI inside the flow
- [ERP integration](https://attendo.me/en/modules/erp-integrations): Odoo, SAP Business One, Business Central and Holded, connected

### Industries that use these modules

- [Manufacturing and industrial plants](https://attendo.me/en/industries/manufacturing)
- [Facility maintenance and services](https://attendo.me/en/industries/facility-maintenance)
- [HVAC and refrigeration](https://attendo.me/en/industries/hvac)
- [Repair and after-sales service](https://attendo.me/en/industries/after-sales-repair)
- [And any other business](https://attendo.me/en/industries)

## Related terms

Processes and automation

### BPM

Business process management

BPM (business process management) is the practice of describing how each process in an organization is done, running it the same way every time, measuring it and improving it.

Processes and automation

### Approval workflow

Approval process · sign-off workflow

An approval workflow is the path a request follows until someone with authority accepts or rejects it: who approves, in what order, within what limits and by when.

Support and service

### Omnichannel

Omnichannel support

Omnichannel means that every channel a customer uses to contact you feeds the same record and the same conversation.

[See all 53 glossary terms](https://attendo.me/en/glossary)

## Shall we look at it with your data?

We will show you how what you just read works in attendo, with your own assets, tickets and customers. If it is not a fit, we will tell you.

- With your operation, not a generic demo
- A real person from our team replies
- No cold calls afterwards

Would you rather talk first?

- Phone [+34 910 053 530](tel:+34910053530)
- Email [sales@attendo.me](mailto:sales@attendo.me)
- Monday to Thursday 9:30 AM to 6:30 PM and Friday 9:30 AM to 2:30 PM (Spain time)