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The World of JScript, JavaScript, ECMAScript …

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Change is inevitable, except from vending machines – a quote from an unknown source but so true. With the release of the Visual J# 2.0 Redist-SE over, the time has come for me to change and look for bigger and brighter challenges. I recently moved to the JScript team at Microsoft IDC. So yes, that would mean going ahead you would read quite a bit on the same at my blogs. Here is a short summary of a few definitions:

What is JScript?

JScript is Microsoft’s implementation of the ECMAScript scripting language. JScript is implemented as a Windows Script engine, which means it can be "plugged in" to any application that supports Windows Script, such as Internet Explorer, Active Server Pages, and Windows Script Host. JScript was first supported in Internet Explorer browser 3.0 and typical file extension of JScript source code files is .js.

Got you, but then what is ECMAScript?

ECMAScript is a scripting programming language, standardized by Ecma International in the ECMA-262 specification. There are three editions of ECMA-262 published, and the work on the fourth edition is in progress.

 

ECMAScript is supported in many applications, especially web browsers where it is is often referred to as JavaScript or JScript. The various dialects typically include their own, different standard libraries, of which some are standardized separately – such as the W3C-specified DOM. Some implementations, of the same have a completely different set of libraries. This means that applications written in one dialect of ECMAScript will not likely work in another, unless they are designed to be compatible

What is JavaScript? How is it different from JScript?

"JavaScript" is actually Netscape Communications Corporation's (and now the Mozilla Foundation's) implementation of the ECMAScript standard.

In addition to other internal implementation differences, the existing version of JScript uses non-generational mark-and-sweep garbage collection whereas JavaScript (the original implementation of which is the SpiderMonkey engine) uses a generational mark-and-sweep system.

Note: Though people often use JScript and JavaScript interchangeably, which is because of the fact that these languages are very similar, it is important to note that neither of them is a simplified version of Java as some may think. Other than incomplete syntactic resemblance and the fact that both JScript/JavaScript and Java can provide executable content in web browsers, the two languages are unrelated.

Would follow up with more soon …

Comments

  • Anonymous
    August 14, 2007
    No I am not talking about coffee

  • Anonymous
    August 14, 2007
    what about javascript.net (in .net 1.1 or 2.0)?

  • Anonymous
    August 14, 2007
    I would briefly talk about the MS flavors of JScript in the next blog.

  • Anonymous
    August 16, 2007
    There are three different types of JScript engines that MS currently offers to the users. In this blog

  • Anonymous
    August 16, 2007
    hello.. i need a prog that i change ''.java'' scripts in.. does someone have any???

  • Anonymous
    August 16, 2007
    adde006 - could you pl elaborate on the exact requirements and what is the result that you desire.

  • Anonymous
    September 06, 2007
    Being a late entrant into the group, I always had questions regarding what’s what of JScript - Managed

  • Anonymous
    November 06, 2007
    That sounds like J# won't ever make it to Java 6 compatibility.

  • Anonymous
    February 22, 2008
    当前MS提供给用户三种不同的JScript Engine,在这篇文章中我们将讨论他们之间的不同,和他们不同的动机.

  • Anonymous
    August 19, 2008
    The comment has been removed

  • Anonymous
    February 13, 2009
    [Nacsa Sándor, 2009. január 20. – február 12.] Komplett fejlesztő környezet Windows kliens és web alkalmazások