LinkedIn has created 2 API sets to provide greater flexibility for developers.
The Javascript API provides a rich and user-friendly library for quickly creating a dynamic user interface in web browsers. It uses OAuth 2 to easily allow users.
While the REST API is a programming language and platform agnostic. It uses the XML / JSON format and its simple. But this requires developers to create their own user interface. It uses OAuth 1.0a to authorize users.
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