JavaScript Prototypes 2025 – The Complete Course

Updated in May 2025. This course now features Coursera Coach! A smarter way to learn with interactive, real-time conversations that help you test your knowledge, challenge assumptions, and deepen your understanding as you progress through the course. Master the foundations and nuances of JavaScript’s prototypal inheritance system in this comprehensive course. You'll gain a deep understanding of how JavaScript handles object creation, inheritance, and the prototype chain, equipping you with practical skills to write more efficient and scalable code. The course begins by introducing key concepts like prototypal inheritance, hidden [[Prototype]] links, and how objects and functions interact with these structures. From there, you’ll explore instantiation patterns including functional, pseudoclassical, and ES6 class-based models, learning how to implement and optimize them through hands-on examples. Next, you’ll dive into the intricacies of the .prototype property, the __proto__ accessor, and their roles in building robust prototype chains. The course includes a practical project to create multi-level inheritance systems using various modern JavaScript approaches. You’ll also compare JavaScript's prototype-based model with class-based languages and composition techniques. This course is ideal for intermediate JavaScript developers looking to deepen their knowledge of object-oriented programming in JavaScript. A basic understanding of JavaScript syntax and functions is recommended. If you're comfortable with objects and functions but want to master inheritance and prototypes, this course is for you.