Java Script

Java Script Introduction

Java Script

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Java Scipt is written in HTML page.
Java Script is a programming language. It is used to validate the client data.
If the the client (or user) data is correct, then the data is submitted to server for further processing.
Java Script is generally run at client side to save processing time of server.
Java Script is easy programming language.
Java Script is based on object oriented programming concepts.
Java Script is written between <script> ... </script> tags.

Three ways of writting Java Script

Method 1: Java Script in Body Tag of HTML

Example 1

<html>
<head>
<title> Display Name </title>
</head>
<body>
<script> 
document.write("Dear Janhvi");
</script>
</body>
</html>

Explanation of the program

Java Script is written in body tag of HTML within <script> tag.
In this program, predfined Java Script object document is used.
Predefined object document calls predefined method write() to display a message on the web page.
Method write("Dear Janhvi") displays the message "Dear Janhvi" on the web page.

Method 2: Java Script in Head Tag of HTML

Example 2

<html>
<head>
<title> Display Name </title>
<script> 
function dispName() {
		document.write("Dear Janhvi");
}
</script>
</head>
<body>
<input type="button" onclick="dispName()" value="click me" />
</body>
</html>

Explanation of the program

Java Script is written in Head tag of HTML within <script> tag.
A function named dispName is defined in the script.
Within the function dispName () , object document is used to display the message Dear Janhvi .
A button is defined within body tag of HTML.
When button is clicked, java scipt function dispName() is called and it displays the message Dear Janhvi on the web page.