needed by API systems is data "<abbr title="also called marshalling, conversion">serialization</abbr>" which is taking data from the code (Python) and converting it into something that can be sent through the network. For example, converting an object containing data from a database into a JSON object. Converting `datetime` objects into strings, etc.

Another big feature needed by APIs is data validation, making sure that the data is valid, given certain parameters. For example, that some...

* 🌐 Add Korean translation for Tutorial - Intro. PR [#2317](https://github.com/tiangolo/fastapi/pull/2317) by [@hard-coders](https://github.com/hard-coders).
* 🌐 Add Chinese translation for Tutorial - Bigger Applications - Multiple Files. PR [#2453](https://github.com/tiangolo/fastapi/pull/2453) by [@waynerv](https://github.com/waynerv).

# Python Types Intro

Python has support for optional "type hints" (also called "type annotations").

These **"type hints"** or annotations are a special syntax that allow declaring the <abbr title="for example: str, int, float, bool">type</abbr> of a variable.

By declaring types for your variables, editors and tools can give you better support.

  - author: Sebastián Ramírez (tiangolo)
    author_link: https://twitter.com/tiangolo
    link: https://www.youtube.com/watch?v=PnpTY1f4k2U
    title: '[VIRTUAL] Py.Amsterdam''s flying Software Circus: Intro to FastAPI'
  - author: Sebastián Ramírez (tiangolo)
    author_link: https://twitter.com/tiangolo
    link: https://www.youtube.com/watch?v=z9K5pwb0rt8
    title: 'PyConBY 2020: Serve ML models easily with FastAPI'

    So, with that type declaration, **FastAPI** gives you automatic request <abbr title="converting the string that comes from an HTTP request into Python data">"parsing"</abbr>.

## Data validation

```Python hl_lines="20-37  39-40"
{!../../../docs_src/path_operation_advanced_configuration/tutorial006.py!}
```

👉 🖼, 👥 🚫 📣 🙆 Pydantic 🏷. 👐, 📨 💪 🚫 <abbr title="converted from some plain format, like bytes, into Python objects">🎻</abbr> 🎻, ⚫️ ✍ 🔗 `bytes`, &amp; 🔢 `magic_data_reader()` 🔜 🈚 🎻 ⚫️ 🌌.

👐, 👥 💪 📣 📈 🔗 📨 💪.

### 🛃 🗄 🎚 🆎

⚙️ 👉 🎏 🎱, 👆 💪 ⚙️ Pydantic 🏷 🔬 🎻 🔗 👈 ⤴️ 🔌 🛃 🗄 🔗 📄 *➡ 🛠️*.

```

</div>

That would work for most of the cases. 😎

You could use that command for example to start your **FastAPI** app in a container, in a server, etc.

## ASGI Servers

Let's go a little deeper into the details.

FastAPI uses a standard for building Python web frameworks and servers called <abbr title="Asynchronous Server Gateway Interface">ASGI</abbr>. FastAPI is an ASGI web framework.

## Opinie

"_[...] I'm using **FastAPI** a ton these days. [...] I'm actually planning to use it for all of my team's **ML services at Microsoft**. Some of them are getting integrated into the core **Windows** product and some **Office** products._"

## Recensioni

"_[...] I'm using **FastAPI** a ton these days. [...] I'm actually planning to use it for all of my team's **ML services at Microsoft**. Some of them are getting integrated into the core **Windows** product and some **Office** products._"

# Alternatives, inspiration et comparaisons

Ce qui a inspiré **FastAPI**, comment il se compare à d'autres solutions et ce qu'il en a appris.

## Intro

**FastAPI** n'existerait pas sans les précédentes contributions d'autres projets.

De nombreux outils ont été créés auparavant et ont contribué à inspirer sa création.

J'ai évité la création d'un nouveau framework pendant plusieurs années. J'ai d'abord essayé de combler toutes les