• Within a functional scope, all variable declarations are hoisted to the top, meaning variables can be used before their formal declaration.
• In other words, a variable declared anywhere in a function exists throughout the entire function and its value is undefined until it's assigned a value. Therefore, the best practice is to declare all variables at the top.

Phases

1. compile
2. execution

key ideas

• nothing is moving anywhere... function and variable declarations are added to memeory during the compile phase
• only declarations are hoisted (not initializations)
• function declarations are also hoisted
• declare variables at top!
• var is initialized with undefined
• let and const are not initialized with anything

# References

https://javascriptweblog.wordpress.com/2010/07/06/function-declarations-vs-function-expressions/ https://codeburst.io/javascript-what-is-hoisting-dfa84512dd28 https://medium.com/javascript-in-plain-english/https-medium-com-javascript-in-plain-english-what-is-hoisting-in-javascript-a63c1b2267a1