Mastering JavaScript Key Concepts: The 3 Pillars of JavaScript
For beginners seeking to grasp JavaScript's core concepts quickly, focusing on its 3 Key Pillars—Prototypes, Closures, and the Event Loop—is essential. These concepts form the backbone of JavaScript's functionality and behavior.

  1. Prototypes Prototypes enable object inheritance, allowing properties and methods to be shared among objects, minimizing redundancy. Example: javascript CopyEdit function Person(name) { this.name = name; }

Person.prototype.greet = function () {
console.log(Hello, my name is ${this.name});
};

const john = new Person("John");
john.greet(); // Output: Hello, my name is John
In this example, the greet method is attached to the Person prototype, so it is shared by all instances of Person.

  1. Closures A closure is formed when a function "remembers" its surrounding lexical scope, even after the parent function has finished executing. Example: javascript CopyEdit function createCounter() { let count = 0; // Variable retained in closure return function () { count++; return count; }; }

const counter = createCounter();
console.log(counter()); // Output: 1
console.log(counter()); // Output: 2
Here, the inner function retains access to the count variable, demonstrating how closures work.

  1. Event Loop The event loop ensures that JavaScript remains non-blocking by managing asynchronous operations like setTimeout or fetch. Example: javascript CopyEdit console.log("Start");

setTimeout(() => {
console.log("Async Operation");
}, 1000);

console.log("End");
// Output:
// Start
// End
// Async Operation (after 1 second)
In this example, the event loop schedules the setTimeout callback to execute after other synchronous code, ensuring smooth execution.

Why These Concepts Matter
By mastering prototypes, closures, and the event loop, you'll build a solid foundation for understanding JavaScript's object-oriented structure, functional programming features, and asynchronous behavior

Author Of article : charles Kamande Read full article