Meanings of the HTML5 Specificaion

[nnn0v0mm]

Hello.
I have a question about a meaning in HTML5 spec.
In this http://dev.w3.org/html5/html4-differences/#changed-elements document, there is an explanation for b element:

The b element now represents a span of text to which attention is being drawn for utilitarian purposes without conveying any extra importance and with no implication of an alternate voice or mood, such as key words in a document abstract, product names in a review, actionable words in interactive text-driven software, or an article lede.

Due to my poor knowledge of English, I couldn't get enough the meaning of this sentences.
The parts which I can't understand are the ones underlined.
Would anybody explain the meaning of those parts?
Thanks.

[JAB Creations]

The b element is different from the strong element.

The b element is visual only whereas the strong element requires auditory tools that read webpages back to people who are partially or completely blind to use certain differences in the auditory playback.

So in other words the b element is purely for visual styling only whereas strong is both audio and visually heavier.

Hope this helps.

[nnn0v0mm]

Thanks JAB.

I'd like to confirm this.

Do you mean that the "implication of an alternate voice or mood" corresponds with the feature of strong element , as with "conveying any extra importance" corresponding with em element ?

If so, the "alternate voice" means aids for visually impaired people and "alternate mood" means aids for other disabled people? (Because I've heard it once before that the alternate voice increases by 120% with the strong element.)

One more question, would you show me the example of the "interactive text-driven software"? Name of a software or image of it, would be appreciated.

Thanks.

[nnn0v0mm]

I was wrong in a part of my last reply.
Please delete the part "as with conveying any extra importance corresponding with em element" in my last reply.