That's what makes it possible to have multiple automatic interactive documentation interfaces, code generation, etc.

OpenAPI has a way to define multiple security "schemes".

By using them, you can take advantage of all these standard-based tools, including these interactive documentation systems.

OpenAPI defines the following security schemes:

* `apiKey`: an application specific key that can come from:
    * A query parameter.
    * A header.

OpenAPI tem uma forma para definir múltiplos “esquemas” de segurança.

Por usá-los, você pode ter vantagens de todas essas ferramentas baseadas nos padrões, incluindo os sistemas de documentação interativa.

OpenAPI define os seguintes esquemas de segurança:

* `apiKey`: uma chave específica de aplicação que pode vir de:
    * Um parâmetro query.

# Security Tools

When you need to declare dependencies with OAuth2 scopes you use `Security()`.

But you still need to define what is the dependable, the callable that you pass as a parameter to `Depends()` or `Security()`.

There are multiple tools that you can use to create those dependables, and they get integrated into OpenAPI so they are shown in the automatic docs UI, they can be used by automatically generated clients and SDKs, etc.

* API usage monitoring systems
* response data injection systems
* etc.

## Simple and Powerful

Although the hierarchical dependency injection system is very simple to define and use, it's still very powerful.

You can define dependencies that in turn can define dependencies themselves.