This video talks about mental model behind variable hoisting and introduces to the concept of Execution context which is the basis of scoping and closures in javascript.
This would act as a starting session to upcoming videos which would talk about other concepts like Scoping ,Closures, this and event loop.
Internals of JS runtime is even more complex but modelling variable hoisting in this manner can help you solve and get to the output of snippets faster thereby helping acing your interviews.
I have only talked about var declarations right now. ES6 let/const, we can discuss in further sessions.
The JS playlist : • Let's Javascript