Google provides a number of client libraries for accessing its services and now JavaScript joins in the long list of other supported languages / platforms, .NET, Go, Python, GWT, Objective-C, Ruby, PHP and Java in which Google's client library is available.
While this is just an alpha release, it is an important step in enabling the integration of Google services in applications that are written in JavaScript.
Web applications are written in JavaScript and this means that now applications that run in the browser can communicate with Google Services directly instead of via the server side. The library works on recent versions of all major browsers, Chrome 8+, Firfox 3.5+, IE 8+, Safari 4+ and Opera 11+.
The library can be used by including a single JavaScript file in your application:
<script src="https://apis.google.com/js/client.js"></script>
This gives access to all supported Google services via an extensive API. The library uses OAuth 2.0 for authenticating with Google, and requires you to obtain an API key for your application via the Google API Console.
You can read more about the JavaScript library here
