What are the diferences of client side programming and server side programming?
When do I use client side and when do I use server side?
Those a web developer need to know both to be effective in writing website?
Client side programming includes any coding or computation or effects or annimation or any sort of interaction your website performs with the user via browser. But server side programming is that which performs all the task in the server only. So the user is unaware of that.
User will only know what happened in the browser but not what happened in the server. Those are background tasks.