Java Reference
In-Depth Information
licensed it to Netscape. JScript shipped with version 3 of the Internet Explorer browser and
was almost identical to JavaScript―it even included all the same bugs and quirks―but did
have some extra Internet Explorer-only features. Microsoft included another scripting lan-
guage called VBScript with Internet Explorere at the same time, although this never really
caught on.
JavaScript (and JScript) was immediately popular. It had a low barrier to entry and was re-
latively easy to learn, which meant an explosion in its usage making web pages dynamic
and more interactive. Unfortunately, its low barrier was also a curse as it meant that people
could write snippets of code without much understanding of what they were actually do-
ing. Code could be easily copied and pasted and was often used incorrectly, leading to lots
of poor code examples appearing all over the Web. JavaScript was also frequently used to
create annoying pop-up adverts and for
browser sniffing
(the process of detecting which
browser was being used to view a web page), and it started to gain a negative reputation.
Netscape and Sun Microsystems decided to standardize the language along with the help
of the European Computer Manufacturers Association, who would host the standard. This
standardized language was called ECMAScript, again, to avoid infringing on Sun's Java
trademark. This caused even more confusion, but eventually ECMAScript was used to refer
to the specification, and JavaScript was (and still is) used to refer to the language itself.
The ECMAScript standard can be difficult to interpret in places, so the implementations of
JavaScript can vary in assorted JavaScript engines. This is why some web browsers behave
differently when running JavaScript programs.
The Browser Wars
By the time Netscape Navigator 4 and Internet Explorer 4 were released, JavaScript had
become incredibly popular. Microsoft had started a lot of hype about the term Dynamic
HTML, or DHTML for short, to refer to the use of JavaScript to make HTML more inter-
active and dynamic. In an attempt to seize upon this popularity, Netscape and Microsoft
tried to add new proprietary features, which lead to different syntaxes being used. This
"arms race" of adding new features to compete became known as the Browser Wars. The
unfortunate downside was that programmers had to write two versions of code to achieve
the same results in each browser. Professional programmers often dismissed JavaScript as
a toy language unsuitable for any serious programming, but this was unfair criticism―the
language wasn't the problem, it was the way it was being implemented and used.
