jQuery is a JavaScript Library that focuses on simplifying DOM manipulation, AJAX calls, and Event handling. It is used by JavaScript developers frequently.

jQuery uses a format, $(selector).action() to assign an element(s) to an event. To explain it in detail, $(selector) will call jQuery to select selector element(s), and assign it to an event API called .action().

  alert("Hello World!");

The above code carries out the same function as the following code:

window.onload = function() {
  alert( "Hello World!" );
  document.getElementById("blackBox").style.display = "none";

Download jQuery

npm bower (solo file) Google CDN
npm install jquery bower install https://code.jquery.com/jquery-3.4.1.min.js https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js

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