Do you know what will be the output of this code? console.log(a); var a = 5;

Why does using a var before its declaration return undefined?

Do you know what will be the output of this code?

JavaScript

console.log(a);
var a = 5;

Show answer and explanation

The answer is undefined.

The declaration var a is hoisted to the top and initialized with undefined. The assignment a = 5 stays where it is, so it hasn’t run yet when console.log executes.

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