global.asax magic

Well have come to accept the fact that this
is microsoft centric world.

I am walking through the examples in
asp.net 1.1 with vb.net (wrox)

i created a basic C# project and the
the following files created were.
assemble.cs
global.asax
web.config
WebForm1.aspx


I get WebForm1.aspx this is the server side page.
but i really need to refreshe what i know
about what the asax does

here is what microsoft says
The Global.asax file, also known as
the ASP.NET application file, is an
optional file that contains code for
responding to application-level events
raised by ASP.NET or by HTTP modules.
The Global.asax file resides in the
root directory of an ASP.NET application.
At run time, Global.asax is parsed and
compiled into a dynamically generated
.NET Framework class derived from the
HttpApplication base class.
The Global.asax file itself is
configured so that any direct URL
request for it is automatically rejected;
external users cannot download or
view the code in it.