Need a brief explanation on web programming languages please!!?

Question

Well basically I know how to use HTML but still learning and applying how to use CSS for styling the web, after digging deeper and deeper into how to build a dynamic good-looking website, I am getting very confused myself. Please try to give me a brief explanation here on each question (I know how to google things but I just need a conclusion from the web guru.) Here are the questions:

1. What jQuery is for? I've seen an example source code which I believe it gives an interactive for the user and the web, then what's the different between jQuery and Javascript?

2. What DOM is for?

3. What AJAX is for?

4. I'm going to use PHP as the server side scripting with MySQL. Is it possible to style the page with the PHP?

5. In order to run a complicated social network website, do I need to know all those mentioning languages/scripts (ajax, jquery, PHP, dom, and so on) including with HTML and CSS of course?

Answer 1

1. When used correctly, jQuery can help you make your website more interactive, interesting and exciting. jQuery is ideal because it can create impressive animations and interactions. jQuery is simple to understand and easy to use, which means the learning curve is small, while the possibilities are (almost) infinite. However, the emergence of Javascript frameworks like jQuery has provided the necessary tools to create beautiful websites without having to worry (as much) about accessibility issues.



Obviously there are cases where a Javascript solution is not the best option. The rule of thumb here is: use DOM scripting to enhance functionality, not create it.



2. While the term “DOM scripting” really just refers to the use of scripts (in this case, Javascripts) to access the Document Object Model or DOM, it has widely become accepted as a way of describing what should really be called “unobtrusive DOM scripting”—basically, the art of adding Javascript to your page in such a way that if there were NO Javascript, the page would still work (or at least degrade gracefully). In the website world, DOM scripting is done using Javascript.



3. Ajax (sometimes called Asynchronous JavaScript and XML) is a way of programming for the Web that gets rid of the hourglass. Data, content, and design are merged together into a seamless whole. Ajax driven applications has very little lag time. The page simply displays what they're asking for. There is very little lag and you don't have to wait for pages to refresh or reload.



4a. PHP and MySQL combine to be an easy yet powerful way to create dynamic web pages that actually interact with your visitors. HTML can create useful and well formatted web pages. With the addition of PHP and MySQL you can collect data from your users, create specific content on the fly, and do many other things that HTML alone can't do.



The beauty of PHP as a language is that it is designed to be used along with HTML. You can use PHP right inside your already existing HTML content, or put HTML tags right inside your PHP coding. When learning PHP you are not making your existing HTML knowledge obsolete, you are instead adding to it to give it more functions and abilities.



PHP is able to preform a number of tasks including printing data, making numeric calculations (such as addition or multiplication), making comparisons (which is bigger, are they equal, etc) and making simple boolean choices. From this you can create more complex loops and functions to make your page generate more specialized data.





4b. MySQL is a relational database system that is used to store information. MySQL can store many types of data from something as tiny as a single character to as large as complete files or graphics. Although it can be accessed by most programing languages, it is often coupled with PHP because they work together with ease.



Information stored in a MySQL database hosted on a web server can be accessed from anywhere in the world with a computer. This makes it a good way to store information that needs the ability to change over time, but also needs to be accessed over the net. Some examples that can utilize MySQL are a web message board or a customer's shipping status, shopping carts etc.



PHP and MySQL complement each other to do with neither can do alone. PHP can collect data, and MySQL can in turn store the information. PHP can create dynamic calculations, and MySQL can provide it with the variables it uses. PHP can create a shopping cart for your web store, but MySQL can then keep the data in a format PHP can use to create receipts on demand, show current order status, or even suggest other related products.



Although PHP and MySQL can each be used independently, when you put them together it opens up countless possibilities for your site. As the internet progresses, it becomes more and more necessary to deliver dynamic content to keep up with the demands of web surfers and their desire to have information instantly delivered to them online. PHP and MySQL can deliver this information on demand.



5. Yes, many websites use a combination of programming languages to deliver interactive content to their users. In my opinion sites using PHP, MySQL combined with AJAX and Javascript do great in the delivery of online interactive web content.



Hope this information use useful to you!

Joel :)

Answer 2

1. jQuery is a javascript library. That means it is JavaScript code that is already written for you to help make certain tasks easier. jQuery in particular is a very elaborate library that almost seems like a new language, but is still technically just JavaScript.



2. DOM is an internal representation of the structure of a web page. Javascript can directly read and manipulate the DOM.



3. AJAX is technically a javascript technique to request or submit information from the internet without loading a new page. AJAX is frequently used to describe "flashy" javascript, like animations, though those things have nothing to do with AJAX.



4. Page styling is done with CSS or with HTML attributes. Either of these can be generated with PHP, though I would recommend using static CSS.



5. jQuery is not necessary (there are other libraries, but libraries aren't necessary), and you might be able to get away without understanding AJAX or the DOM. Also, there are alternatives to PHP, but you'll need to know some server-side language, and PHP is a fine choice. Knowing Javascript (including AJAX and the DOM) will allow you to make your pages "cooler" with some nice features that can't be done in straight HTML.

Answer 3

Here are your answers. By the way what do you use to make your webpages dynamic ? Dynamic means that the content of the site is generated by itself (database/files/users) and it can be updated by the user. You need to use server side scripting to create dynamic websites with technologies like ASP.Net, JSP, Ruby on Rails, Perl, PHP etc.



1. JQUERY is a javascript based framework that is used to exchange ligh weight data between the browser and the server. This is usually used when implementing AJAX (see AJAX below)



2. DOM is the document object model. Every Web page is a document. The browser window needs to know the structure of the document to be able to parse it and display components. It describes the levels for each element inside the document. It is extensively used in javascript for client side validations, effects etc



3. AJAX is asynchronous xml and java script. In traditional web applications when you "submit" (click a button) the page reloads and you see your changes taking effect. With AJAX you dont see this reload, it just happens (Rate a video on you tube) or (Like some article on facebook)



4. You will need to use CSS to style your page. styling is not a part of any server side scripting language. ITs graphics, css and html



5. My advice to you is "Dont make a social networking site" but if you wanna go ahead probably you will need a good understanding of how AJAX works and how to implement these. You do not need to learn all this as you can use javascript libraries or high level frameworks like Prototype, Scriptaculous, DOJO and others who already use this :)



All the best and I hope it helps.

Answer 4

CGI is the way of passing data between web server process and serverside scripts. CGI played a huge role, but at some point lost it's position to in-process p-code implementations like PHP. Now it got second breath with FastCGI mechanism, which becomes popular since it overcomes some limitations and bottlenecks imposed by in-web-server-process scripting.