Application programming interfaces, or APIs, provide a method for connecting

your website to a third-party Web service like Dropbox, Google, or GitHub.

It's kind of like connecting to a database for data.

You set up a connection, make a request, and receive the results.

These results are primarily returned in either XML or JSON.

Both XML and JSON are human readable and computer readable, and

just about any programming language comes with standard libraries to parse XML and

JSON quickly and easily.

This promotes the easy sharing of data on the web.

There is no single universal API.

Each site has its own, and not all sites offer an API for you to use.

The first step for using any API is to look up the documentation.

The documentation should tell you how to connect, and what actions are available.

Let's take a look at the GitHub API.

Let's search for GitHub API.

Before using any API, you should make sure to check the Terms and Conditions.

Make sure that your planned usage does not violate the Terms of Service.

According to the GitHub API documentation, all API access is over HTTPS,

and accessed from the api.github.com URL.

All data is sent and received as JSON.

There are three ways an API may allow a connection.

First, an API can have a public endpoint without any authentication needed.

Simply request a URL, and receive the results.

Second, an API can allow basic authentication, such as username and

password, or other credentials.

Finally, there's token based authentication like OAuth.

The application asked to share specific information between the applications.

And when the user chooses to grant permission,

a token is stored on the user's machine.

GitHub supports all three of these methods,

depending on what you're trying to do.

Although, most of the time,

GitHub requires that you pass at least the username as the user agent.

You won't be able to read private data, or

update your account without some sort of authentication.

Username alone is not enough.

For unauthenticated requests,

the rate limit allows you to make up to 60 requests per hour.

Unauthenticated requests are associated with your IP address, and

not the user making the request.

For a request using basic authentication, or

OR, you can make up to 5,000 requests per hour.

Let's make our first request.

Launch the workspace attached to this video, and open the console.

You can also use a terminal or command line directly from your computer.

Using the console will allow us to quickly test an endpoint.

Let's type curl

https://api.github.com /users,

and then /treehouse.

We receive a JSON feed of the treehouse user information.

You can issue a get request to the root end point to get all

the endpoint categories that the API supports.

Let's go back to the documentation and look at a few more endpoints.

GitHub gives us a lot more than just user information including issues.

Projects, pull requests, repositories and more.

Let's take a look at repositories.

We want to list user repositories.

Remember, you won't see private repositories, unless you're authenticated.

Let's try the same treehouse request, but this time, we'll add /repos to the end.

Now we receive a JSON feed of public repositories.

Take some time to familiarize yourself with some of the documentation and

endpoints that the good hub API supplies.

The Getting started section of the guide is a great place to start.