JScript & javascript are both scripting dialects that facilitate development of webpages. JScript is just like javascript with simple distinction in things & features revealed. JScript is reinforced and delivered by Ms and may be perform best only on IE where as javascript was started by netscape and can perform across all internet explorer continually.
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JavaScript JavaScript is a scripting language developed by Netscape Communications designed for developing client and server Internet applications. Netscape Navigator is designed to interpret JavaScript embedded into Web pages. JavaScript is independent of Sun Microsystem's Java language. Back to the top JScript Microsoft JScript is an open implementation of Netscape's JavaScript. JScript is a high-performance scripting language designed to create active online content for the World Wide Web. JScript allows developers to link and automate a wide variety of objects in Web pages, including ActiveX controls and Java programs. Microsoft Internet Explorer is designed to interpret JScript embedded into Web pages. The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

The biggest difference now between JavaScript and JScript are all of the additional commands that JScript supports that allow access to ActiveX and the local computer. These commands are intended for use on intranet sites where you know the configuration of all of the computers and that they are all running Internet Explorer.There are still a few areas remaining where JavaScript and JScript differ in the means that they provide to perform a particular task. Except in these situations the two languages can be considered to be equivalent to one another and so unless otherwise specified all of the references to JavaScript that you see will also usually include JScript.