How do hints work in word?

Question

Programming

I enter the text and write "programming" instead of " programming ", it underlines the wrong word for me and corrects it when pressed. How it works?
And then there are commas. I write " Hello, how are you? " and he emphasizes to me, saying that after hello there should be a comma. How is such a function implemented?
Are these ordinary dictionaries or neural networks? If the first option, then how are these dictionaries compiled?

Answer 1

Dictionaries with a paradigm of the most frequent words and with chains of tokens by parts of speech and punctuation marks.
A comma is put
A comma is not put
All the basic rules are in dictionaries.

Answer 2

First from google
hunspell.github.io
https://nuspell.github.io/
https://github.com/AbiWord/enchant
https://github.com/bakwc/JamSpell
jazzy.sourceforge.net
https://www .cs.hmc.edu/~geoff/ispell.html
aspell.net