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codeWithNithin
codeWithNithin

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How to create a variable in JS?

To create a variable in JS, we have 3 keywords, let, var and const.
where let and const is introduced in ES6, and var is the old keyword used to declare the variables.

For Example:

let firstName = 'Nithin';
const age = 23;
var lastName = 'kumar';
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here let and var behaves in the same way, that is, we can change the value of the variable which is declared as let or var.

For example:

let firstName = 'Nithin';
var lastName = 'kumar';

firstName = 'Varsha';
lastName = 'kumari';
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But const is a keyword, which doesnt change its variable value once it is being assigned.

For example:

const age = 23;
age = 24; // will give error
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Top comments (3)

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jonrandy profile image
Jon Randy ๐ŸŽ–๏ธ

You can also create one without using any of let, var, and const if you're not in strict mode

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marzelin profile image
Marc Ziel • Edited

You can also create one without using any of let, var, and const if you're not in strict mode

You should mention that this is an antipattern.

Also, when you declare a function you're creating a variable since a function is just a value in JS and can be overridden.
What's interesting about this is that functions are block-scoped so technically JS had block-scoped variables before ES2015.

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codewithnithin profile image
codeWithNithin

ok