// Copying Value: let a = 10; let b = a; // 10 b = b + b; // 20 // Expected behaviour!! // Now, What's the behaviour of this: let x = [1, 2, 3, 4]; let y = x; y.pop(); // [1, 2, 3] // Simple but what's in x - [1, 2, 3] // How? Let's know how? Fir...