The document discusses various methods for accessing and consuming external data with jQuery including:
1) RESTful web services and consuming REST APIs with jQuery's AJAX methods by making GET and POST requests.
2) Common data formats for APIs like XML, JSON, and RSS and examples of each.
3) Consuming the Twitter REST API with jQuery to get user tweets, post new tweets, and search tweets.
4) Twitter's @Anywhere solution which makes it easy to add Twitter features like follow buttons and tweet widgets to applications.
5) Demonstrating the Facebook JavaScript SDK and APIs for features like login/logout and posting.