Should beginners use let or const in JavaScript?

Use const when you do not need to reassign the variable, and let when the variable needs a new value later.

What does reassignment mean?

Reassignment means pointing an existing variable name to a new value, such as count = count + 1.

Why practice JavaScript variables before functions?

Functions pass, return, and update values, so variables are the foundation for understanding function behavior.

JavaScript practice

JavaScript Variables Practice

JavaScript variables are easier when you practice the difference between names, values, and reassignment. These questions focus on let, const, and simple expressions.

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How to practice JavaScript variables

JavaScript variable practice teaches the difference between a name, a value, and a binding. That difference matters when choosing let, const, and reassignment.

Track the value after every statement. If const feels confusing, separate reassignment of the binding from mutation of an object or array stored in that binding.

What to focus on

let, const, and block scope
Reassignment and updated values
Primitive values compared with arrays

Example practice questions

Try these samples, then continue into the JavaScript Practice Labfor guided browser-based practice.

Which keyword declares a variable that can be reassigned?

Answer: let

Which keyword declares a value you do not plan to reassign?

Answer: const

After let count = 2; count += 3; what is count?

Answer: 5

What type of value is stored by const name = 'Mia'?

Answer: A string

Can a const array have items pushed into it?

Answer: Yes, the array can mutate even though the binding cannot be reassigned.

What is the value of total after let total = 1; total = 4?

Answer: 4

Which keyword creates a block-scoped variable?

Answer: let or const