API stands for **Application Programming Interface**. An API is a protocol for communication between different applications.

For example, a software developer might use a weather API like [darksky](https://darksky.net/forecast/-74.0059/us12/e) to fetch weather information for their weather reporting app. 


# How do API keys work?
In order to call an API, the "caller" has to send unique information as an identifier to the API service provider. This identifier is called an **API key**. 

There are two main functions of an API key:
 
**Recognition:** Allows the service provider to identify the calling user/application. It also allows the service provider to track calls by the individual caller, monitor trends, and ensure the caller doesn't "abuse" the resource.

**Access control:** Allows the service provider to grant access to the calling user/application.



<h2>How do API keys work?</h2>
In order to call an API, the "caller" has to send unique information as an identifier to the API service provider. This identifier is called an **API key**. 

There are two main functions of an API key:
 
**Recognition:** Allows the service provider to identify the calling user/application. It also allows the service provider to track calls by the individual caller, monitor trends, and ensure the caller doesn't "abuse" the resource.

**Access control:** Allows the service provider to grant access to the calling user/application.



What is an API key?

Unique API keys identify and control access for applications calling an API, ensuring secure communication.