Difference between JavaScript and PHP

Last Updated : 26 May, 2022

In this article, we will know about Javascript & PHP, along with understanding their significant differences.

A long time before, most people used to think PHP is a server-side language and Javascript as client-side language as it was only executed in web browsers. But after V8, Node and other frameworks came, Javascript is capable of doing a lot of things Php used to. Since we can handle both front-end and back-end through Javascript now, It’s considered as more powerful than PHP.

JavaScript: It is the most popular lightweight, interpreted compiled programming language. It is also known as a scripting language for web pages. It is well-known for the development of web pages, many non-browser environments also use it. JavaScript can be used for Client-side developments as well as Server-side developments.

Syntax:

<script>
    document.write("JavaScript syntax");
</script>

You can place the tags, anywhere within your web page, but it is normally recommended to keep it within the <head> tag. This tag tells the browser to start interpreting all the text between these tags as JavaScript code.

Example 1: This example describes the Javascript basic example to print the text for the specified time using the for loop.

HTML

<!DOCTYPE html>
<html>
<title>Basic JavaScript Example</title>
<body>
    <h2>A simple JavaScript program</h2>
    <script>
        var n;
        n = 5;
         
        // JavaScript uses the var keyword to declare variables.
        // An equal sign is used to assign values to variables.
         
        for(var i = 0; i < n; i++) {
            document.write("GeeksforGeeks " + "<br>");
        }
    </script>
</body>
 
</html>

Output:

A simple JavaScript program
GeeksforGeeks 
GeeksforGeeks 
GeeksforGeeks 
GeeksforGeeks 
GeeksforGeeks

Example 2: This example illustrates Javascript getElementById() method where element_id is used to get the text.

HTML

<!DOCTYPE html>
<html>
<title>Javascript Example</title>
<style>
    #gfg {
        font-size: 40px;
        color: #006400;
    }
</style>
 
<body>
    <h2 id="gfg">GeeksforGeeks</h2>
    <button onclick="myFunction()">Click Me!</button>
    <script>
        function myFunction() {
            document.getElementById("gfg").innerHTML = "Hello Geeks!";
        }
    </script>
</body>
 
</html>

Output:

Getting the element using getElementById Method

PHP: PHP is an acronym for Hypertext Preprocessor, which is a server-side scripting language designed specifically for web development. PHP can be easily embedded in HTML files and HTML codes can also be written in a PHP file. Like Javascript, PHP can also be written in HTML code and in the .php file extension itself too. But it requires a server to run, so you won’t be able to see an output of the code. in a simple manner.

Syntax:

<?php
    echo "Hello Geeks!!!";
?>

Steps to run the PHP code:

You can install Xampp or any other local server app. After installing Xampp, name your code file with the extension .php and move your Html or Php file to htdocs folder of xampp. Now, open xampp, run apache, and SQL server, & now go to localhost with your file URL (type localhost/folder name/filename.php or localhost/filename.php in your browser) and there you can see the output. PHP code starts with <?php and ends with ?>. This is to tell the compiler/server that the PHP language starts here.

Example 1: This example describes the PHP for loop to display the repeated output.

HTML

<!DOCTYPE html>
<html>
<title>PHP Code inside the HTML</title>
<body>
    <?php
  
     // Declare variables using $ symbol
     $str= "GeeksforGeeks";
     $x = 5;
 
     // PHP for loop
     for( $i = 0; $i< $x; $i++ ) {
          echo ("GeeksforGeeks");
     }  
    ?>
    <!--This code will print GeeksforGeeks 5 times on front end-->
</body>
 
</html>

Output:

GeeksforGeeks
GeeksforGeeks
GeeksforGeeks
GeeksforGeeks
GeeksforGeeks

Difference between Javascript vs PHP:

S.No.	Javascript	PHP
1.	Javascript does the job for Both Front-end and Back-end.	PHP is used mostly for Back-end purposes only.
2.	Javascript is synchronous but it has a lot of features like callbacks, promises, async/await which allows implementing asynchronous event handling	PHP is synchronous, It waits for IO operations to execute.
3.	Javascript can be run in browsers and after Node, we can also run it in the Command line.	PHP requires a server to run. Cannot run without a server.
4.	Javascript can be combined with HTML, AJAX, and XML.	PHP can be combined with HTML only.
5.	Javascript is a single-threaded language that is event-driven which means it never blocks and everything runs concurrently.	PHP is multi-threaded which means it blocks I/O to carry out multiple tasks concurrently.
6	Javascript code is less secure.	PHP code is highly secure.
7	Javascript requires an environment for accessing the database.	PHP allows easy and direct access to the database.
8	JavaScript is used to create real-time games and applications, mobile applications etc.	A PHP program is used to create dynamic pages, send cookies, receive cookies, collect form data, etc.
9	JavaScript is case sensitive in case of functions.	PHP is not case sensitive in case of functions.
10	Brendan Eich in 1995 developed JavaScript.	Rasmus Lerdorf in 1994 developed PHP.
11	JavaScript files are saved with .js extension.	PHP files are saved with an extension .PHP