**FastAPI** has a very powerful but intuitive **<abbr title="also known as components, resources, providers, services, injectables">Dependency Injection</abbr>** system.

It is designed to be very simple to use, and to make it very easy for any developer to integrate other components with **FastAPI**.

## What is "Dependency Injection" { #what-is-dependency-injection }

* **Fast to code**: Increase the speed to develop features by about 200% to 300%. *
* **Fewer bugs**: Reduce about 40% of human (developer) induced errors. *
* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.

/// note | Technical Details

You could also use `from starlette.responses import HTMLResponse`.

**FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette.

///

### `Response` { #response }

The main `Response` class, all the other responses inherit from it.

You can return it directly.

                    corresponding JSON. But if the data in the object returned is not
                    valid, that would mean a violation of the contract with the client,
                    so it's an error from the API developer. So, FastAPI will raise an
                    error and return a 500 error code (Internal Server Error).

                Read more about it in the

  </properties>
  <issueManagement>
    <system>jira</system>
    <url>http://jira.codehaus.org/browse/MNG</url>
  </issueManagement>
  <mailingLists>
    <mailingList>
      <name>Maven Developer List</name>
      <subscribe>******@****.***</subscribe>
      <unsubscribe>******@****.***</unsubscribe>
      <post>******@****.***</post>

It streamlines the process of **building**, **deploying**, and **accessing** an API with minimal effort.

It brings the same **developer experience** of building apps with FastAPI to **deploying** them to the cloud. 🎉

FastAPI Cloud is the primary sponsor and funding provider for the *FastAPI and friends* open source projects. ✨

### El abbr da una frase completa y una explicación { #the-abbr-gives-a-full-phrase-and-an-explanation }

* <abbr title="Mozilla Developer Network – Red de Desarrolladores de Mozilla: documentación para desarrolladores, escrita por la gente de Firefox">MDN</abbr>
* <abbr title="Input/Output – Entrada/Salida: lectura o escritura de disco, comunicaciones de red.">I/O</abbr>.

Es vereinfacht den Prozess des Erstellens, Deployens und des Zugriffs auf eine API mit minimalem Aufwand.

Es bringt die gleiche **Developer-Experience** beim Erstellen von Apps mit FastAPI auch zum **Deployment** in der Cloud. 🎉

FastAPI Cloud ist der Hauptsponsor und Finanzierer der „FastAPI and friends“ Open-Source-Projekte. ✨

```JSON
{
  "username": "johndoe",
  "email": "******@****.***",
  "full_name": "John Doe",
  "disabled": false
}
```

<img src="/img/tutorial/security/image09.png">

If you open the developer tools, you could see how the data sent only includes the token, the password is only sent in the first request to authenticate the user and get that access token, but not afterwards:

<img src="/img/tutorial/security/image10.png">

  </properties>
  <issueManagement>
    <system>jira</system>
    <url>http://jira.codehaus.org/browse/MNG</url>
  </issueManagement>
  <mailingLists>
    <mailingList>
      <name>Maven Developer List</name>
      <subscribe>******@****.***</subscribe>
      <unsubscribe>******@****.***</unsubscribe>
      <post>******@****.***</post>