JavaScript need not be a scary thing to approach. It can bring a deeper level of interactivity and functionality to otherwise bland HTML, and has a fully developed standard for web-developers to follow. This means you do not have the same cross-browser compatibility issues that often creep out from under the carpet of DHTML.

OOP can make a language easier to tackle, by breaking a program up into 'parts' to make up the whole. The easiest way to explain this may be with an example. You can look at an OOP as if you were building a desk instead of a program: the parts may be the legs, the top, perhaps a hutch and a set of drawers. Without the legs, it is just a slab of wood and put them together and you have something to put a glass of water on. If you want to get fancy, add the hutch -- which would look silly without the rest of the desk! The important thing to remember is that you must not use any part of the legs to build that hutch, and you cannot cut up the slab you are using for the top and use it to make the drawers.

Something important to note is that JavaScript is unable to stand on its own like Java. It is a text-based language that must be placed within HTML, to be read by the browser and interpreted so the instructions can be performed. Because of this, JavaScript is also very easy to edit: simply alter the text, and re-run the HTML. For simple applications, this is ideal; for complex applications, this is limiting. When writing in Java, the HTML document generally does little other than 'call upon' the applet (Java application). JavaScript is geared entirely towards web-development while Java, because of its amazing versatility, is geared to almost any use you have in mind.

Cascading Style Sheets (CSS)
do some pretty wonderful things to your Web page. However, they cannot add interactivity--such as images changing as you move your mouse; sections of a page appearing and disappearing; content changing dynamically and complex calculations being
performed automatically.

Enter JavaScript--a scripting language that lets you do the near impossible, while simultaneously
being quick and easy to learn. JavaScript is not Java. The latter is a language designed to run on
any platform, anywhere. JavaScript, on the other hand, only works in a Web browser.
JavaScript is embedded within your HTML page, and is interpreted by the browser as the pageloads. This reduces the load on the Web server, as opposed to CGI scripts.

What are the alternatives to Javascript?


+++ Jscript: According to Microsoft, JScript is an "object-oriented and interpreted scripting
language that operates within the purview of the browser". One of JScript's biggest
advantages is that it builds on and enhances many of Internet Explorer's existing capabilities.
But this power comes at a price--JScript will only work in Internet Explorer, and is not
supported by other browsers. One of JScript's biggest advantages is that it builds on and
enhances many of Internet Explorer's existing capabilities. But this power comes at a price--
JScript will only work in Internet Explorer, and is not supported by other browsers.

+++ VBScript: It's Microsoft's attempt to help Visual Basic programmers make the transition to
Web programming. If you're familiar with Microsoft's Visual Basic family of programming
languages, you'll quickly recognize the syntax and structure of VBScript. However, it is
supported only by Internet Explorer.

+++ ActiveX: Developed by Microsoft, ActiveX refers to a "set of strategic object-oriented
program technologies and tools." The concept here is pretty simple--an ActiveX component is
a self-sufficient program that can be run anywhere on a Windows or Macintosh system. This
component is also known as an ActiveX "control". ActiveX controls can be downloaded as
small programs or animations for Web pages, or can be created using programming tools like C, Visual Basic or PowerBuilder. One of the technology's main advantages is that it can be
reused by different applications--so an ActiveX control created for use in a Web page can
also be used in your Visual Basic application with no modification required.

+++ Java: Java can be used to write both applications and "applets". Java applets can perform
calculations, interactive animations, file input/output and other simple tasks without having to
send a user request back to the server.

+++ Flash: Flash allows Web designers to create resizable and extremely compact user
interfaces, illustrations, animations and other dazzling effects for their site. If you're looking
for interactivity, this is one technology that is well worth investing in--it lets you produce Web

To begin JavaScript,you will need to have a few things.Here they are:

You should know how to use HTML and be able to edit your HTML documents.
You will need to have a web browser that supports JavaScript. You should use Netscape version 3 or later, or Microsoft Internet Explorer version 3.02 or later. If you use IE, I recommend IE4 because IE3.x is not compatible with all of the scripts.

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