JavaScript is a scripting language which is similar in syntax to Java. The JavaScript code is embedded within the HTML file and is interpreted by the client browser. JavaScript brings interaction to the web pages. Using JavaScript, it is possible to customize HTML documents on the fly, write event handlers for elements on a page, validate data at the client side and perform other client-side computations.

To view the various JavaScript examples, you need a JavaScript capable browser which you already have. I have tested my code only using Internet Explorer 3. If you find that any of the samples are not working properly, please mail me.

About the language

JavaScript is a dynamically typed language. This means that data types in Javascript are not fixed but are automatically converted from one to other as required. For example, you could say myData = 10; in one line initializing the value of myData to an integer, and in the next line, say myData = "Hello World!" setting the value of myData to a string. Javascript will automatically convert data types within expressions if necessary. So if you say myData = "10" - 2;, you will end up with 8. Javascript automatically converts "10" to 10 and does the integer subtraction. If you are wondering why Javascript does not convert 2 to "2" instead, it is because the operator - is not defined for strings and hence "10" - "2" does not make any sense. This brings us to another interesting situation. The operator + is defined both for numbers and strings. So will 10 + "20" return 30 (10+20) or "1020" (“10″ + “20”). It turns out that whenever you mix numbers and strings and use the + operator, Javascript will always convert everything to string before evaluating. Thus 10 + "20" is the same as "10" + "20" and will evaluate to "1020"

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JavaScript is case sensitive. Thus foo is not the same as Foo.(By the way, can someone tell me what foo actually means?)

Due to the security built into JavaScript, it is highly unlikely that JavaScript code can do damage on your system. So you can run them without worry.

My JavaScript samples

All the samples given here are small and simple. If you find any of them useful, feel free to copy it on your page. Drop me a mail and include the location of your page if possible. If you like this site, consider giving me a link.