JavaScript Fundamentals · Conditions · Lesson 7 of 48
Comparison and Logical Operators
Concept
Comparison and Logical Operators
===, !==, <, and > compare values. && (and), || (or), and ! (not) combine multiple conditions together.
Always prefer === and !== over == and != — the triple-equals versions compare both value and type, avoiding surprising automatic type coercion.
- Explain the core idea behind Comparison and Logical Operators.
- Predict output before running a change.
- Test one realistic and one unusual input.
- Use the result to make the next decision.
- 1. Read one concept.
- 2. Change the example.
- 3. Run, compare, and explain.
- 4. Complete the challenge below.
Good to know
|| is also commonly used for a fallback value, like let name = input || "Guest";, though ?? is safer when 0 or an empty string are valid values.
Self-check before continuing
Without looking at the example, describe what changes when you modify one input in Comparison and Logical Operators. Then reopen the editor and prove your explanation with a small test.
You are ready to continue when you can predict, test, and explain the result.
Your turn
Write a condition that checks if a number is between 1 and 100 using &&.
Ask about this lesson or your next move. The guide explains the path without taking the work away from you.
Ready for the next lesson?
Mark this lesson complete when you have finished the exercise.
Console