Welcome to another video from Yenkna PCs. This time we're going to look at another
website language called JavaScript. Now, I'm gonna let my A.I. take over here you
go. Take it away. JavaScript, often abbreviated as JS, is a
high-level, dynamic, weakly typed, prototype-based, multi-paradigm,
and interpreted programming language. Alongside HTML and CSS, JavaScript is
one of the three core technologies of World Wide Web content production. It is used
to make webpages interactive and provide online programs, including video games.
The majority of websites employ it, and all modern web browsers support it
without the need for plug-ins by means of a built-in JavaScript engine. Each of
the many JavaScript engines represent a different implementation of JavaScript
all based on the ECMAScript specification, with some engines not
supporting the spec fully, and with many engines supporting additional features
beyond ECMA. As a multi-paradigm language, JavaScript
supports event-driven, functional, and imperative (including object-oriented and
prototype-based) programming styles. It has an API for working with text, arrays
dates, regular expressions, and basic manipulation of the DOM, but the
language itself does not include any I/O, such as networking, storage, or
graphics facilities, relying for these upon the host environment in which it is
embedded. Initially only implemented client-side in
web browsers, Java Script engines are now embedded in many other types of host
software, including server-side in web servers and databases, and in non-web
programs such as word processors and PDF software, and in runtime environments
that make JavaScript available for writing mobile and desktop applications
including desktop widgets. Although there are strong outward similarities between
JavaScript and Java, including language name, syntax, and respective standard
libraries, the two languages are distinct and differ greatly in design; JavaScript was
influenced by programming languages such as Self and Scheme. Beginnings at Netscape: In 1993, the National
Center for Supercomputing Applications (NCSA), a unit of the University of
Illinois at Urbana-Champaign, released NCSA Mosaic, the first popular graphical
web browser which played an important part in expanding the Grove
World Wide Web. In 1994, a company called Mosaic Communications was founded in
Mountain View, California and employed many of the original NCSA Mosaic authors
to create Mosaic Netscape. However, it intentionally shared no code with NCSA
Mosaic. The internal codename for the company's browser was Mozilla, which
stood for "Mosaic killer", as the company's goal was to displace
NCSA Mosaic as the world's number one web
browser. The first version of the Web browser, Mosaic Netscape 0.9, was released in late 1994. Within four months it had
already taken three-quarters of the browser market and became the main
browser for the Internet in the 1990s. To avoid trademark ownership problems with
the NCSA, the browser was subsequently renamed Netscape Navigator in the same
year, and the company took the name Netscape Communications. Netscape
Communications realized that the Web needed to become more dynamic. Marc
Andreessen, the founder of the company believed that HTML needed a "glue
language" that was easy to use by Web designers and part-time programmers to
assemble components such as images and plugins
, where the code could be written directly in the Web page markup. In 1995,
the company recruited Brendan Eich with the goal of embedding the Scheme programming
language into its Netscape Navigator. Before he could get started,
Netscape Communications collaborated with Sun Microsystems to include in
Netscape Navigator Sun's more static programming language Java, in order to
compete with Microsoft for user adoption of Web technologies and platforms.
Netscape Communications then decided that the scripting language they wanted
to create would complement Java and should have a similar syntax, which
excluded adopting other languages such as Perl, Python, TCL, or Scheme. To defend
the idea of JavaScript against competing proposals, the company needed a prototype.
Eich wrote one in 10 days, in May 1995. Although it was developed under the name
Mocha, the language was officially called LiveScript when it first shipped in
beta releases of Netscape Navigator 2.0 in September 1995, but it was renamed
JavaScript when it was deployed in the Netscape Navigator 2.0 beta 3 in
December.
The final choice of name caused confusion, giving the impression that the language
was a spin-off of the Java programming language, and the choice has been
characterized as a marketing ploy by Netscape to give JavaScript the cachet
of what was then the hot new Web programming language.
Nombas did pitch their embedded Web page scripting to Netscape, though Web page scripting was not
a new concept, as shown by the ViolaWWW Web browser. Nombas later switched to
offering JavaScript instead of C-- in their ScriptEase product and was part of
the TC39 group that standardized ECMAScript. JavaScript and Java: A common
misconception is that JavaScript is similar or closely related to Java. It is
true that both have a C-like syntax (the C language being their most
immediate common ancestor language). They also are both typically sandboxed (when used
inside a browser), and JavaScript was designed with Java's syntax and standard
library in mind. In particular, all Java keywords were reserved in original
JavaScript, JavaScript's standard library follows Java's naming conventions,
and JavaScript's Math and Date objects are based on classes from Java 1.0,
the similarities end there. Java and JavaScript both first appeared on May
23rd 1995 , but Java was developed by James Gosling of Sun Microsystems, and
JavaScript by Brendan Eich of Netscape Communications.
The differences between the two languages are more prominent than their
similarities. Java has static typing, while JavaScript's typing is dynamic.
Java is loaded from compiled bytecode, while JavaScript is loaded as human-
readable source code. Java's objects are class-based, while JavaScript's are
prototype-based. Finally, Java did not support functional programming until
Java 8, while JavaScript has done so from the
beginning, being influenced by Scheme.
Thank You A.I. This was a video describing JavaScript and when it does on websites.
I hope you found this video educational. Please, hit that like button. If you
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