JavaScript
is a scripting language most often used for client-side web development. It was the web development. It was the originating dialect of the ECMAScript standard. It is a dynamic, weakly typed, prototype-based language with first-class functions. JavaScript was influenced by many languages and was Javadesigned to look like , but be easier for non-programmers to work with
"JavaScript" is a
trademark of Sun Microsystems. It was used under license for technology invented of Sun Microsystems. It was used under license for technology invented and implemented by Netscape Communications and current entities such as the Mozilla Foundation
Java is an Object Oriented Programming (OOP) language created by James Gosling of Sun Microsystems. JavaScript was created by the fine people at Netscape. JavaScript is a distant cousin of Java. It is also an OOP language. Many of their programming structures are similar. However, JavaScript contains a much smaller and simpler set of commands than does Java. It is easier for the average weekend warrior to understand.
You may be wondering what OOP means by now. Object Oriented Programming is a relatively new concept, whereas the sum of the parts of a program make up the whole. Think of it this way: you are building a model car. You build the engine first. It can stand alone. It is an engine and everyone can see it's an engine. Next you build the body. It can also stand alone. Finally, you build the interior including the seats, steering wheel, and whatnot. Each, by itself is a object. But it is not a fully functioning car until all the pieces are put together. The sum of the objects (parts) make up the whole.
Continuing with the model car example, when you built the engine, you didn't use any of the parts that would later build the seats (a 350 four-barrel engine with a seat belt sticking out if the piston would look pretty silly). The point is that all the parts that made up the engine were of a certain class of parts. They all went together. Ditto with the body and then the interior.
The point is that in these languages, you build objects out of classes of commands to create the whole. Understand the terminology? Good. Moving along...
Now let's talk about how Java and JavaScript differ. The main difference is that Java can stand on its own while JavaScript must be placed inside an HTML document to function. Java is a much larger and more complicated language that creates "standalone" applications. A Java "applet" (so-called because it is a little application) is a fully contained program. JavaScript is text that is fed into a browser that can read it and then is enacted by the browser.
Another major difference is how the language is presented to the end user (that's you when you're surfing). Java must be compiled into what is known as a "machine language" before it can be run on the Web. Basically what happens is after the programmer writes the Java program and checks it for errors, he or she hands the text over to another computer program that changes the text code into a smaller language. That smaller language is formatted so that it is seen by the computer as a set program with definite beginning and ending points. Nothing can be added to it and nothing can be subtracted without destroying the program.
JavaScript is text-based. You write it to an HTML document and it is run through a browser. You can alter it after it runs and run it again and again. Once the Java is compiled, it is set. Sure, you can go back to the original text and alter it, but then you need to compile again.
Java applets run independent of the HTML document that is calling for them. Sure, they appear on the page, but the HTML document did little more than call for the application and place it. If the programmer allows it, oftentimes parameters can be set by the HTML document. This includes
Answered by
Om Prakash
, an ibibo Master,
at
5:56 PM on June 06, 2008