do i have to install jquery to use it code example

Example 1: how to download jquery

You have quite a few options

You can get the whole source
Uncompressed dev: https://code.jquery.com/jquery-3.4.1.js
Compressed production: https://code.jquery.com/jquery-3.4.1.min.js
You the simply save the code into a Javascript file and include it in the usual way
<script type="text/javascript" src="jquery.js"></script>

Or point to a CDN, such as Google's
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>

You can get it using NPM, Yarn or Bower
npm install jquery
yarn add jquery
bower install jquery

You can even get the latest builds from GitHub
git clone git://github.com/jquery/jquery.git

Example 2: html include jquery

<!-- Wrap inside the head tag -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>

Example 3: jquery version how

if (typeof jQuery != 'undefined') {  
    // jQuery is loaded => print the version
    alert(jQuery.fn.jquery);
}

Example 4: html how to add jquery

<!--You can insert Jquery into HTML with the <script> tag in the <head>-->
<!--Insert the next line of code into your <head> tags.-->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script> <!-- jquery (help with javascript) -->

Tags:

Php Example