Status Updates From Introduction to the Theory ...

Skip to chapter 2.

Skip the rest of chapter 0.

Ah! I'll complete these topics in depth by watching these videos,
https://www.youtube.com/playlist?list...

"A reduction is a way of converting one problem to another problem in such a way that a solution to the second problem can be used to solve the first problem. Such reducibilities come up often in everyday life, even if we don’t usually refer to them in this way."

"To make this Turing machine into a decider, we need to ensure that the al-
gorithm tries only finitely many derivations."

Skimming through. I think decidability, in the context of languages, is a language that can be interpreted by an NFA or a DFA.