What are the differences between const and let in JavaScript?

What are the differences between const and let in JavaScript?

In JavaScript, 'let' allows you to declare variables that can be reassigned, while 'const' is for variables that cannot be reassigned.

Can you give me an example of using both?

Sure! With 'let', you can do this:

let x = 10;
x = 20; // This is fine

And with 'const':

const y = 30;
y = 40; // This will throw an error

Are there any scope differences between them?

Yes! Both 'let' and 'const' are block-scoped, meaning they are only accessible within the block they are defined in, unlike 'var' which is function-scoped.

When should I use const over let?

You should use 'const' when you want to ensure that a variable's reference won't change, which helps prevent accidental reassignments.