What is the difference between client side programming and server side programming?
Client side programming is code that is executed on the user’s computer (the client). Examples of this would be: JavaScript and ActionScript. Server side programming is code that is executed on the server computer. Examples of this would be PHP, ASP, and even C++ in some cases. The most important thing you must know to understand the difference is that client side code is first downloaded on the users computer before it is executed. For example, a flash movie must first be downloaded before it is executed. Thus, any code that runs in the flash movie (ActionScript) will execute on the user’s computer. With server side code, the server does the processing first and then sends it to the client. A good way to visual this is a CAPTCHA image. The CAPTCHA image is generated randomly on the server first and then it is sent to the user (aka the client). The client never sees the code that generated the CAPTCHA — all he/she receives is an image. And by the way, the importance is paramount here.
