Some code to demonstrate hoisted variable in JavaScript.

hoistedVariable.js

function hellKitchen() {
    if (true) {
        var knd = "chef"; // will I be chef?
    }
    
    console.log(knd); // yes, I'm a chef due to variable hoisting
                      // and 'knd' is accessible anywhere in 'hellKitchen'
}

// equivalent snippet of code
function hellKitchen101() {
    var knd;
    if (true) {
        knd = "chef";
    }
    
    console.log(knd); // yes, I'm a chef
}

// what if
function hellKitchen102() {
    if (false) {
        var chuckNorris = "chef";
    }
    
    console.log(chuckNorris); // oops, 'chuckNorris' is 'undefined'
                              // no error raised, why? Tip: 'undefined' != 'not defined'
}

hellKitchen();
hellKitchen101();
hellKitchen102();