I started to look at creating a plugin for a web-based application as related to some potential project work.  It once again through me into a world I never heard of and knew nothing about.  Do you know what MVC is?  No, then we are on the same level.  MVC stands for Model View Controller and it is a way to build web applications.  If you'd like a quick, but good, introduction into MVC specifically for ASP.NET, then I recommend this video.  Not for the faint of heart, or those not familiar with a little web programming.