Downloading Same Security Updates

From: Steven (shoobydu_at_comcast.net)
Date: 03/01/04 

Date: Mon, 1 Mar 2004 07:20:57 -0800

I have Win 2K Professional.

For the past couple of weeks, I have been prompted to
install Windows security patch 811493 every time my Norton
Security Program downloads a security update. Last I
counted, it was 16 times!

Is this necessary? Do the Windows security patchs change
daily and if so, why not give them a different number?
What is(are) the reason(s)?