Why Use ReactJS? Benefits, Uses, and Advantages

Why Use ReactJS?

What Problem Does React Solve?

In plain JavaScript, you manage the DOM manually. Consider a simple "items in cart" counter.

let count = 0;
const countEl = document.getElementById("cart-count");
const badgeEl = document.getElementById("cart-badge");

function addItem() {
  count = count + 1;
  countEl.innerText = count;
  badgeEl.innerText = count;
  if (count > 0) {
    badgeEl.style.display = "block";
  }
}

Every place the count appears needs its own update line. Miss one, and the screen shows two different numbers. This class of bug the data says one thing, the screen says another is what React eliminates.

In React, you write the count once as data, and every place that displays it stays in sync automatically.

Why is it Used?

A Note on Expectations

React is not automatically faster than plain JavaScript, and it is not the right tool for a simple static page. A three-page brochure website does not need React. React earns its place when the interface has a lot of changing data and repeated UI patterns.