Allowing a learner to use the keyboard to navigate around a published Adobe Captivate project is a large part of ensuring that your project is accessible (you learn about accessibility and Section 508 compliance during our live, online, 2-day advanced Captivate class).
However, if you've added a Table of Contents and/or a playbar to your Captivate project, you might want to ensure that only slide items can be accessed via tabbing.
As an experiment, add a TOC to a project (via Project > Table of Contents), publish it and view it in your web browser. As you press the [tab] key, you'll notice that you can go down the TOC and then across the playbar.
Back in Captivate, display the Publish Settings dialog box via the File menu. Select (check) Restrict keyboard tabbing to slide items only.
Republish the project. This time when you [tab] through the lesson, the TOC and playbars are not accessible, but screen objects are.
Note: If you publish the project as HTML5, the learner will end up in the browser's Address bar after all of the slide items have been tabbed.