how to do automatic sms generation???

Question

what methods for automatic sms message generation sometimes your mobile phone receives some sms from the mobile service provider about some events. When i try to do this in my mobile application using C#.NET, i realize that i need to make a automatic sms message generation module in order to automatically send sms message to customers according to a specific time. But i do really have no ideas what methods or topics i need to refer to in order to make this........so far what i learn about mobile application is creating a mobile website that allows mobile client devices to access and perform actions, which means we code mainly for the client side.....so i really wonder whether i can code for the server side in order to make automatic sms message generation happens??? or actually there is a person at the server side who manually type in the message and send to the client?? if so, how to implement it in .NET???.......i am kinda blurred of this.........anyone can help??? Thanx.......