Choose the first available value

Use || for a simple fallback value.

Official sourceECMAScript — binary logical operatorsReviewed: 2026-08-26

STEP 1 · LEARN

How it works

The || operator returns the first operand when it is truthy; otherwise it evaluates and returns the second. An empty string is falsy, so the fallback text is chosen.

Correct example

const customLabel = '';
const label = customLabel || 'Implicit';
console.log(label);

label receives the text “Implicit”.

Common mistake

const label = customLabel && 'Implicit';

With && and a falsy first operand, the result remains the empty string.

STEP 2 · APPLY

Your exercise

Declare label as customLabel || “Implicit” and print label.

script.jsJAVASCRIPT

Isolated consoleisolated

Preparing the runtime…

Run the code to see the result.

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STEP 4 · CHECK

What needs to pass

0%not checked

customLabel and label are declared with const.
label uses customLabel || the fallback.
The output is Implicit.

Explain the solution logic

The operator selects the fallback at runtime; the text is not printed separately.

How it works

Your exercise

Write and run the code

What needs to pass