> For the complete documentation index, see [llms.txt](https://splootcode.gitbook.io/api-scheduled-apps/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://splootcode.gitbook.io/api-scheduled-apps/~/changes/8vPDTVYGeehLNTeV7Gar/api-apps/what-apis-look-like.md).

# What APIs look like

As we said in [Introduction to APIs](/api-scheduled-apps/~/changes/8vPDTVYGeehLNTeV7Gar/api-apps/introduction-to-apis.md), there's two parts composing an API, a request and a response.

## API requests

An API request must contain certain elements that are necessary for clients to communicate with it. These elements typically include:

* **Request Methods**\
  APIs can use different HTTP methods such as GET, POST, PUT, DELETE, PATCH to perform different operations on the server.
* **URL Path**\
  APIs typically use URLs (Uniform Resource Locators) to identify the resources that they provide access to. The URL path specifies the location of the resource within the API.
* **Request Body**\
  APIs can use request bodies to transmit data from the client to the server. The request body can contain data in different formats such as JSON, XML, or plain text.
* **Headers**\
  APIs use headers to transmit metadata along with the request or response. Headers can contain information about the content type, authorization, caching, and other aspects of the request.

## API responses

Similarily, responses can contain different elements.

* **Query Parameters**\
  APIs can use query parameters to filter, sort, or search for specific data within a resource. Query parameters are specified in the URL.
* **Response Body**\
  APIs can use response bodies to transmit data from the server to the client. The response body can contain data in different formats such as JSON, XML, or plain text.
* **Status Codes**\
  APIs use status codes to indicate the result of the request. Status codes can include success codes, error codes, and other types of codes.
* **Authentication and Authorization Mechanisms**\
  APIs can use various authentication and authorization mechanisms to ensure that only authorized clients can access the resources.