OAuth is a simple, secure, and quick way to publish and access protected data (photos, videos, contact list). It's an open authorization model based primarily on existing standards that ensures secure credentials can be provisioned and verified by different software platforms.
In other words, OAuth allows you to share your private resources stored on one site with another site without having to hand out your user name and password.
For a visitor to your site, OAuth is completely transparent. The user experience will be specific to the implementation of both the site requesting access and the one storing the resources, and will adjust to the device being used (web browser, mobile phone, PDA, set-top box).
Example user flow:
A developer has created an application which will allow his users to represent their presence using the Yahoo Status web service. Once the developer signs up for an OAuth API Key and Secret (provided by Yahoo), they may access Yahoo's OAuth API to establish the credentials used to access this data from Yahoo Status. When a user interacts with the developer's application, they are redirected to Yahoo's authorization page, where they sign into their Yahoo account, then grant the application access to their Yahoo Status data. A user-authorized token is returned to the application which can be used to access this data.
For an illustration of the OAuth authorization flow, check out the Yahoo OAuth Quick Start Guide.
In order to communicate with their target user's Yahoo services through OAuth, developers must first authorize requests using Yahoo OAuth.
Here are the steps you take to enable users to access your application:
Questions and suggestions on the OAuth API are discussed on the Yahoo OAuth Developer Community forum. If you have questions or need technical support, please use this forum.
The Create Consumer Key API makes it easy for developers to programmatically generate a Yahoo OAuth Consumer Key. A Consumer Key is required for services that need to access Yahoo APIs. It can be used with web and desktop applications that leverage the OAuth Authorization Model. This API makes it easy for developers to efficiently distribute their applications to 4th parties.
Yahoo's OAuth implementation is fully compliant with OAuth Core 1.0 and the OAuth Session Extension draft (1). In order to support OAuth in a scalable way, Yahoo proposed and helped create the OAuth Session Extension together with AOL and Google. The extension is currently being added to all the major OAuth client libraries as well as the Y!OS SDK. For more information on the standard, visit: http://oauth.net/.