In JavaScript, mutable objects are dynamic elements that allow post-creation changes and modifications.

As an object-oriented programming (OOP) language, JavaScript has various functions, methods, and properties for objects. Objects are mutable or immutable — mutable objects' values can change, whereas immutable objects remain unchanged once created.

For example, consider an object called dog:

let dog = {

  name: “Snoopy”,

  breed: “Beagle”,

  age: 4,

}; = “Scooby-Doo”;

dog.breed = “Great Dane”;

dog.age = 7;

Here, dog is a mutable object. You can change its name, breed, and age properties by giving them new values — Snoopy to Scooby-Doo and 4 to 7.

Mutability allows web developers to manipulate data dynamically without changing other properties. However, modifying multiple values in a single object can lead to undesired results and bugs, such as accidentally altering the wrong property and leading to incorrect data, or causing issues when other parts of the code rely on the original, unmodified values. As a result, it's essential to understand mutability before writing code.

Visit the Webflow blog to learn more about JavaScript and other OOP languages.

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