JavaScriptQuestion 16 of 36
Differences between not defined and undefined?
Answer out loud or in your head first, then compare.
Answer
undefined:
JavaScript
let x;
console.log(x);output:
undefinedThe variable exists but has no value.
not defined:
JavaScript
console.log(x);without a declaration:
ReferenceError: x is not definedHow did it go? Be honest — “Not yet” puts the question on your review list.
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