Java script has a very simple and easy to learn syntax. You can write any JavaScript statement and execute it by placing it within the <script>... </script> tags in HTML documents. The <script> tag indicates to the browser that it has reached a point where all the text between these <script> tags are sets of statements that need to be executed. A simple example of Java Script syntax is as follows:
<script>
JavaScript code
</script> Let us illustrate the syntax of JavaScript with a simple program that prints: “Hey there!”.
<html>
<body>
<script>
<!--
document.write("Hey there!")
//-->
</script>
</body>
</html>The output produced by this code will be
Hey there!
White Spaces, Line Breaks and Semicolons
JavaScript ignores irrelevant spaces, tabs, and new lines within a program. This allows free formatting and unrestricted levels of indentations to suit one's readability needs.
Simple statements in JavaScript and many other programming languages like java, C, etc. usually end with a semicolon. In JavaScript, you may omit semicolons if each instruction is placed on separate lines. For example, the following code explains the whole procedure described above.
<script>
var x = 15
var y = 25
</script> When multiple statements are placed are on a single line, then semicolons are necessary to determine the end of the statements.
<script language = "javascript" type = "text/javascript">
var x = 15; var y = 25; var z = 30
</script>