DHTML, JAVA, JAVASCRIPT? I need some details....

[tabsquare]

Is DHTML a language? or is it a composition of JavaScript and css? Does Java(not javascript) has something to do in it?

What is actually the best to create client-side dynamic pages?
I know JAVA is used to create applets but I am not sure of wich is the most powerful....

Also, wich are the newer versions of all the above languages?


That's a lot of things I asked.
Thanks for helping a beginner in client-side scripting!

[aspen]

Java is a full fledged compiled language. You could make a browser in java, an os in java, a word processor etc.

Javascript is loosely based off java and is a client side scripting language for the internet. This means that the browser executes the code - not the server.

DHTML is just the application of javascript and css to make a dynamic page. Its basically a buzz word.

CSS isn't a scripting language - its just a way of organizing and categorizing the elements on your page.

Java Applets are "mini programs" coded in java. These executed and downloaded by the clients computer as well but they aren't really considered client side scripting I don't think.

A java applet also has quite a few restrictions placed on it for security reasons and as such an applet cannot do everything an application can.

Java as a language is comparable to C or C++ if that helps.

The reason applets exist is because they are cross platform compatible. Java doesn't actually run like other programs do it is run by a virtual machine. Think of it like this.

If you have a mac and a pc you can't use a program from one on the other because they aren't compatible.

Now you can't use Mac's Java Virtual Machine on a PC and vice versa - but once you have the VM installed you can run the same java program on either system.

On the internet you're dealing with so much variety that in order to use a technology like an applet the language needs to be portable - so we use java applets.

[sbdi]

Also there is jsp which is a server side version of java, you can use jscript (microsoft version of javascript) for ASP instead of Visual Basic

[tabsquare]

Hi,
But now I am not sure wich to learn. Should I learn Java(that permits me to create desktop applications, jsp pages and web applets) or DHTML(For wich I need JavaScript and CSS knowledge)?

My first objective is to learn the most powerful for (web) client-side scripting. Wich?


Thanks

[aspen]

if you want to do client side scripting you need to learn javascript.

[tabsquare]

mmm yes, sorry I meant something that let's you create client-side dynamic applications.

Anyway, I think I will first learn JavaScript and then see how this is implemented in DHTML technology.....

Thanks

[sbdi]

now this is just my opinion of course but i think learning javascript is quite pointless now, there are hundreds of sites out there that will provide everything and anything you could possibly need dHTML for, you would be better off learning jsp

[aspen]

being able to customize your scripts and write your own is why you need to learn javascript - besides its pretty easy.

[Scot-Bot]

Jedi master, Java has nothing to do with Javascript whatsoever. The fact that they have similar sounding names is purely coincidental.

Javascript was initially called LiveScript, and only became "Java"Script when Java came out, so as to ride on its coat tails. A marketing ploy, nothing else!

It's true, they do have a similar syntax. But, then so does C, Perl, etc. And Javascript is not based on any of these.

You can also use a combination of Java and Client Side JavaScript (CSJS) in Netscape known as LiveConnect, but it's important to stress that Javascript is not the scripting version of Java. They don't have the same relationship that Visual Basic and VBScript have!

As for DHTML, this is merely HTML 4+, Javascript, Cascading Style Sheets (CSS) and the Document Object Model (DOM). The DOM comes in three flavours: level 0 (which means browser specific models, such as "document.all" for IE and "document.layers" for NN), and level 1 and 2 which are known as W3C-DOMs and are supported by IE5+ and NS6.

Netscape 6 is the most advanced browser there is, and is therefore capable of producing the most sophisticated DHTML scripts currently possible on a full-release product.

IE6 should cover more support for the W3C-DOM when it's finally released, but don't be surprised if you still have to make adjustments for NS6. This is not necessarily because NS6 is not up to the job, but more likely because Microsoft want to do things their way or not at all.

Ok. Scot-Bot.

[BC]

Originally posted by Scot-Bot
Jedi master, Java has nothing to do with Javascript whatsoever. The fact that they have similar sounding names is purely coincidental.

That's not entirely 100% correct. I quote direct from Danny Goodman's Dynamic HTML - The Definitive Reference (p.11) :

When Navigator 2 made its debut, it provided built-in client-side scripting with JScript. Despite what its name might imply, the language was developed at Netscape, originally under the name LiveScript. It was a marketing alliance between Netscape and Sun Microsystems that put the "Java" into the JavaScript name. Yes, there are some striking similarities between the syntax of JavaScript and Java, but those existed even before the name was changed.

So it wasn't purely coincidental - it was a deliberate, pre-ordained move between two of the biggest Net behemoths at that point in time.

IE6 should cover more support for the W3C-DOM when it's finally released, but don't be surprised if you still have to make adjustments for NS6. This is not necessarily because NS6 is not up to the job, but more likely because Microsoft want to do things their way or not at all.

......... Or the fact that at the moment, even after a number of months, Netscape 6's market share is barely under 2%.

[Scot-Bot]

Thanx for the insight into the Netscape and Sun alliance for world dominance BC, but it still remains true that Javascript is not a cut-down version of Java. "Despite the name, Javascript and Java have almost nothing do to with one another," says Negrino and Smith in Javascript for the World Wide Web: Visual Quickstart Guide 3rd Ed.

However, while you're probably right about the usage of NS6 (even tho web stats can be a bit dubious at the best of times) NS6 still has the best support for web-standards that there's been to date. Just a pity the browser isn't 100% stable, but it will improve.

From what I'm given to believe the NS6 usage of my own org's website is around 11%, with only approximately 50% of users using a Microsoft browser at all.

[aspen]

Jedi master, Java has nothing to do with Javascript whatsoever. The fact that they have similar sounding names is purely coincidental.

Please point to me where I said it did.

I said its loosely based of java - and it is. If you know both you'd know there are alot of syntax and structure similarities.

Its not much - thats why I used the word "loosely" but its subjective so I guess I shoulda spelled things out huh.

[Scot-Bot]

Aspen, I wasn't having a go at you, because what I understood what you meant.

But the word "based" can be misconstrued, since JS is not based on or off, loosely or otherwise, Java, even tho they share similarities.

I mean there is also a likeness with some things in Perl, but you wouldn't say JS was based off it, because that would be misleading.

That's all I meant. I didn't mean to offend if I did.

[BC]

I think we're all getting too picky and off the original topic of this thread..................

Personal recommendation : if you like doing HTML/JavaScript/graphics design, then DHTML and JavaScript is useful.

For serious programming + dollars, Java/JSP is the way to go.

[freakysid]

Here's my two bob's worth... A roadmap for becoming supreme ruler of the internet in little tinsy steps:

(A) You want to create hip and groovy web pages. In order of importance you need to know:
1) HTML
2) CSS
3) JavaScript and the DOM

As someone pointed out 2) and 3) are considered DHTML because when used together they make boring old HTML web pages do neat and silly things (like mouse-over image swaps, etc).

(B) Next you want to learn how to serve pages that are dynamically created on the web server. The choice of server-side scripting language depends on the web server platform you are using. You can learn one or all of the following;
ASP, ColdFusion, PHP, Perl, JSP.

(C) Once you are using a server side scripting language you will want to hook your scripts up to a database so you can store and retrieve vast amounts of information such as subscribers, customers, product catalogs, etc. You will need to choose a relational database (MySQL, PostgreSQL, MS SQL, Sybase, Oracle, etc) and the language that all these use a derivative of SQL (strucured query language).

(D) OK you are getting pretty close, but only one thing stands in your way of total world domination - Systems integration. In order to control the entire universe, you need to be able deploy vast armies and move finances globally right from your web site (or conduct financial transactions, stock ordering systems, etc). To be able to integrate your web based applications into the wider enterprise information systems (such as inventory systems) you need to interface your web services with other system services using Java or COM or CORBA platforms and powerful compiled languages such as Java or C++ or ( :giggle: VB).

[tabsquare]

Hi

Since I already took the B step, I think I have to go back to the A. What now I need to learn JavaScript primarly is a book or something. I could learn it going through source codes but that would be hard .

I saw different online free e-books/tutorials, but I am afraid that none of them will teach me all and good.
Any f you know where I can find a free good book/tutorial to learn JavaScript? If no...well....I think I'll just have to buy a real book.