Server Side Include (SSI) are directives that are placed in the HTML pages. These directives are evaluated on the server when the pages are served. When the existing pages are served, they help you add the dynamically created content to it. It eliminates the need of CGI or other dynamic technology.

The use of this technology is depended upon the nature of the pages. Some pages are more static and some needs to be recalculated every time the page is served. Adding small pages of information is done efficiently by SSI. If the pages need more dynamic generation, then some other technology can be used.

More specifically if we say this is a server side scripting language which is used exclusively for the web. Its primary use is including the contents of one file into other while the latter is been served by the web server. Mostly the SSI is preferred for the  simple automation task. If there needs some more complex server side scripting then other language are used for eg. Perl, PHP, ASP, ASP.NET, JSP, Java, CFML, Python, and Ruby.

If we look at the Syntax it is quite simple and the directives are placed in HTML comments so that if SSI is not enables then the users will not see the SSI Directives on the page. The users will have to look at the source of the page if they are eager to know what is used.

Syntax : <!--#directive parameter=value parameter=value -->

For SSI to Work you need a file in text format called .htaccess in the directory where you put the HTML file. The .htaccess file which is present should contain the three important command lines:

Options Indexes FollowSymLinks Includes

AddType application/x-httpd-cgi .cgi

AddType text/x-server-parsed-html .html

Listed below are some of the basic SSI Directives :

Echo : This directive is useful in inserting certain data in variable form in the HTMLPage.

Include: The most used directive which allows to include the content of the one document to other.

FSize: this directive is used to display the size of the specified document.

Flastmod : This Directive is used for displaying the date when the specified was last modified

Exec: Useful to execute the External executable file.

Config: This directive is useful for setting up certain HTML output options.

ODBC: One of the most use full directives which is useful in quering and updating the ODBC Database.

Email : This directive takes care of the sending and receiving email whenever HTML page is accessed or HTML form is submitted.

As there is a technology at Server side there exists a technology at the client side called Client Side Includes. CSI are the HTML includes achieved on the client Side through use of iFrames, JavaScript. These methods have a big shortcomings than the server side includes : they rely on the client support from the respective technologies.

Bookmark To:

Web application are very interesting to build. But most of the web application and too slow and the user gets bored up waiting for the reply from the server. This is the reason why AJAX is here. You just click on the AJAX driven application and you get the result at the moment without the lag time

Ajax is a shorthand for Asynchronous JavaScript and XML. It is a group of interrelated technologies used on client side. Using this technology the applications can retrieve data from the server asynchronously. It does not disturb the behavior of the existing page. No need to refresh time to time. Due to the use of AJAX the web application are now fully decorated with animations.

What technologies form AJAX?

HTML and CSS which is helpful in styling.

DOM (Document Object Model) with JavaScript for dynamic display and interaction

XML, XSL for manipulation and data interchange

Ajax is not a new technology, instead it is a new way of looking towards web applications, a technology that is stable and mature.

Features of Ajax.

Asynchronous content loading:

With the use of this technology you don’t have refresh the webpage now and then. It ensures that applications can exchange data with the server, independent of the loading and reloading of the entire web page. Hence the result is very interactive and interesting which ties the users to the applications.

Increased interactivity:

Using the AJAX toolbox the developers can build RIA( Rich Internet Application). The visitors will just love the type of interactive application they are using. Such application render fast.

Reduced loading time.

Applications developed using this technology needs less time to load since only a part of the site is loaded at a time. This helps to reduce the server traffic as well, bandwidth usage is less and website performs well

One thing which should be remembered is that the Ajax is not supported by every browsers. It requires JavaScript, It means that it will not run in the devices and the browsers that does not support JavaScript

Bookmark To: