Schema.org Property: speakable - Indicates sections of a Web page that are particularly 'speakable' in the sense of being highlighted as being especially appropriate for text-to-speech conversion. Other sections of a page may also be usefully spoken in particular circumstances; the 'speakable' property serves to indicate the parts most likely to be generally useful for speech. The speakable property can be repeated an arbitrary number of times, with three kinds of possible 'content-locator'...| schema.org
Uncover what Google Search is, how it works, and the approach Google has taken to make the world’s information accessible to everyone.| www.google.com
The Google Search Essentials make up the core parts of what makes your web-based content (web pages, images, videos, or other publicly-available material that Google finds on the web) eligible to appear and perform well on Google Search.| Google for Developers
Follow our general guidelines for structured data. These guidelines will help your structured data be eligible for rich Google Search results.| Google for Developers