JSONP, or json with padding, is a technique hack that allows you to retrieve json content from a remote page, and pass that content to a Javascript function, without falling foul of the browser XSS same origin policy.
Idno has had a JSON view of it’s data objects for some time, but up until now it has been hard to call that data from within javascript, unless you were doing it from the same domain.
So, I sent Ben a pull request which adds JSONP support to Idno core, together with some enhancements to the data the standard JSON view provides.