Robots read the Internet.
Search engines are robots and do nothing but read what's on websites.
Machine readers read websites and say aloud what's on them for the benefit of blind surfers.
Machines are simple and dumb. They don't require much, but what they require, well, they really require.
Here are a few tips to make your site more readable by machines and humans too by learning a few code concepts!
Code
Machines don't know a headline from a picture unless they are told. Html code is what tells what it's reading.