A popular protocol used today in virtually every single website any where on the World Wide Web is that of the Client Side Include. This protocol is exactly as is stated in that all functions occur on the client’s browser. These are scripts and are used everywhere from things like cookies that keep you signed into your favourite website while you add content, to AJAX created content.
Client Side Includes is used for many different reasons and while it is possible for someone to simply turn them off in their browser, doing so will also take away from their ability to use a website. While it is possible for anything created by CSI to be created on the server side, this ends up becoming more of a resource hog than necessary. Furthermore, in the case of things like cookies, they drastically reduce the potential of security risks. The biggest difference one could point out between the two is that of a cookie while logged into check your mail, versus a certificate for access to a secure server when making a credit card purchase online.
Furthermore, the use of client side includes is necessary for the interaction with a website. The server would otherwise only know what to do when a direct command is given to it. However with the use of a CSI, a user can drag and drop a menu, or open up another page without having to put forth any major effort. The scripts allow for the client browser to use some of its own processing power to ease the strain on the server and in exchange, interaction between the website visitor and the website itself is made possible.
It is important to remember that while server side languages like PHP are able to communicate with the server and tell it how to process the data for the website visitor, it cannot be physically used by the client as this would then pose a security risk to the actual server. The CSI instead allows for the communication to occur between the two environments.
The concept of Web 2.0 is based on this premise and without the ability to use client side includes, there would be no Web 2.0, there would be no website analytical data, there would be no affordable way to log into a website but most importantly, you would not have things that you have become accustomed to like photo albums, the sharing of information and data on the web and much more as all of these processes require the implementation of client side includes. Unless the page is written completely by hand in nothing but pure HTML, chances are that it is in someway shape or form using a client side include to allow your website visitors and the server to interact with each other.
Original Authors: Nick
Edit Update Authors: M.A.Harris
Updated On: 30/01/2009