let x = 20;
let y = 30;
let z = 40;

let x = 20; 
let y = 'G'; 
let z = "GeeksforGeeks"; 
  
console.log("x: ", x); 
console.log("y: ", y); 
console.log("z: ", z);

x:  20
y:  G
z:  GeeksforGeeks

let x = 20, y = 30, z = 40;

let x = 20, 
    y = 'G', 
    z = "GeeksforGeeks"; 
  
console.log("x: ", x, "\ny: ", y, "\nz: ", z);

x:  20 
y:  G 
z:  GeeksforGeeks

const [var1, var2, var3] = [val1, val2, val3];

const [x, y, z] = [20, 'G', "GeeksforGeeks"]; 
  
console.log("x: ", x, "\ny: ", y, "\nz: ", z);

x:  20 
y:  G 
z:  GeeksforGeeks