Immutable data types are those whose values cannot be changed once they are created. Any operation on an immutable data type will create a new value rather than modifying the existing one. Examples of immutable data types in JavaScript include numbers, strings, and booleans.
Mutable data types, on the other hand, are those whose values can be changed after they are created. Operations on mutable data types directly modify the existing value. Examples of mutable data types in JavaScript include arrays and objects.
Here is a concise and structured answer differentiating between immutable and mutable data types using JavaScript:
<!DOCTYPE html> <html> <body> <h2>Immutable vs Mutable Data Types</h2> <script> // Immutable data types let number = 5; // Number let string = "Hello"; // String let boolean = true; // Boolean // Attempting to modify immutable data types number = 10; // Creates a new value, does not modify the original string = "World"; // Creates a new value, does not modify the original boolean = false; // Creates a new value, does not modify the original console.log(number); // Output: 10 console.log(string); // Output: "World" console.log(boolean); // Output: false // Mutable data types let array = [1, 2, 3]; // Array let object = { name: "John", age: 25 }; // Object // Modifying mutable data types array.push(4); // Modifies the original array object.age = 26; // Modifies the original object console.log(array); // Output: [1, 2, 3, 4] console.log(object); // Output: { name: "John", age: 26 } </script> </body> </html>
In the above example, we demonstrate the difference between immutable and mutable data types. We first declare variables for each data type and then attempt to modify them. For immutable data types, assigning a new value creates a new value without modifying the original. However, for mutable data types, we can directly modify the original value.