Wikipedia Viewer CORE Problems

So i got some problems with my Wikipedia Viewer.
Every time i search something i get an error message: XMLHttpRequest cannot load Origin is not allowed by Access-Control-Allow-Origin.
I already figured out that this has something to do with COREs. So my Questions are why i get this messages, how can i fix this and where can i learn more about that topic?

Here is the full explanation. You need to have your string end with &callback=?

url:‘’ + searchTerm + ‘&callback=?’

As already mentioned, you need to add the callback=? parameter.

Besides that, $.get() seemingly requires a dataType parameter. According to the documentation it is optional, but I found that adding it solves the problem. You could of course also use getJSON instead.

Thank you all for your help. It worked