how to declare a variable js

JavaScript
//let and var are both editable variables and can be changed later on in your program;
let dog = 'Woof';
//dog is equal to the string 'Woof';
dog = false;
//You can changed the value of dog now because it was defined with let and not const;

let cow = 'Moo';
//cow is equal to the string 'Moo';
cow = true;
//You can change the value of cow later on because it is not defined with const;

//const is used when declaring a variable that can't be changed later on -- const stands for constant;
const pig = 'oink';
//This assigns the string 'oink' to pig which can not be changed because it is defined with const;
pig = 'snort';
//Above throws an error
//Good Job you now know how to declare variables using JavaScript!!!var variable1 = "some variable content";// let & var are both editable variables:
var cow = 'moo';
let pig = 'oink';
cow = 10;
pig = 10;
// const is a permanent variable; you cannot change it.
const uncuttableGrass = '\/\/';
uncuttableGrass = '___';
// above throws an error
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