In traditional web sites and applications, the browser connects to the server (e.g. “antonischristofides.substack.com”), makes a request (e.g. “Please give me the page with path ‘/p/how-javascript-became-popularpart-e65’”), and the server provides a response in HTML; e.g. something like
<h1>How JavaScript became popular—part 5</h1>
<p class="subtitle">The frameworks changed the way web applications work</p>
...
If the user clicks on a link, the browser makes a new request and receives another response in HTML, i.e. another web page, which replaces the page that was previously visible.
Modern web applications written with the so-called “JavaScript frameworks” work differently. A JavaScript program that runs on the browser makes a request and receives a structured response like this:
{
title: "How JavaScript became popular—part 5",
subtitle: "The frameworks changed the way web applications work",
...
}
The JavaScript program reads the data from the response and creates the HTML itself, which it then shows on the browser.
The result is web applications that are much faster and more pleasant to use for the user. You can feel the difference when you use different kinds of web applications.
There are three JavaScript UI frameworks, i.e. libraries, that help programmers write such modern applications: React (2013), Vue.js (2014), and Angular (2016). These were the last thing that contributed to JavaScript’s exploding popularity.
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