Excellent and very clear article - The only thing which I would add is that by default cookies are only sent for the domain which created them
Therefore if the cookie was written by test.go4expert.com it could not be read by forums.go4expert.comThe way of fixing this is to set the domain of the cookie to the base domain, then both forums.go4expert.com and test.go4expert.com could access the information
The code to add would be :-
Response.Cookies("domain").Value = DateTime.Now.ToString()
Response.Cookies("domain").Expires = DateTime.Now.AddDays(1)
Response.Cookies("domain").Domain = "go4expert.com"
I've tripped over this before and thought it was worth clarifyng.