Attribute: xmlns

The xmlns attribute, when added to the sys:job-categories tag, lets the system know which vocabulary to use in evaluating the code that you have entered, so that it will generate the proper output.

Should you be aware of the vocabulary that you are using, you can enter the URL of some page that contains a definition of it.

Otherwise, do not add the attribute to the tag at all, and the system will automatically use the default vocabulary.

In the end, if you do decide to use the attribute, simply enter the tag into the desired page's "Source" editor window as follows:

<sys:job-categories xmlns="http://www.example.org/xhtml" />