To answer the specific question in your title, the term you're looking for is "web page life cycle".
ThisThe ASP.NET Page Life Cycle Overview page on MSDN describes the cycle for an ASP.NET page. The terms are general (for the most part), but the details of the actions are specific for ASP.NET.
The MSDN goes into the full detail, but the page life-cycle has 7 stages:
- Page request
- Postback event handling
and the page goes through them all and finishes at stage 7 when it's viewed.
At each stage events are fired that allow the developer to run their own code appropriate to that stage.