Ontos is a provider of tools that aggregate content that is semantically related to content that already exists on a website or blog. Their API returns semantic metadata in RDF-based formats for existing text content. The API uses natural langugage processing to recognize entities and the relations between them. With the API, uses can link their text content with metadata coming from over 500,000 web documents. Full documentation is not publicly available.
The following is a list of how-to and tutorial content that matched your search term. ProgrammableWeb's how-to content comes from two sources; full-blown tutorials that we publish ourselves and other highly relevant tutorials that we find elsewhere on the Web. This list represents on combination of both tutorial types and if you go to ProgrammableWeb's API University, you'll not only be able to find more, they are organized based on your role (API providers or developers who consumes APIs). If you know of a tutorial that would be of interest to the ProgrammableWeb community, we'd like to know about it. Be sure to check our guidelines for making contributions to ProgrammableWeb.