first 'baby' day

i am new to this board so please excuse my dumb questions....i have been doing some research and keep reading that the day you have the 'sex that gets you preggo' is not necessarily the day that the egg and sperm unite to create the baby....about how many days after sex does the 'baby' actually happen....(see, i told you it was a dumb questions...

also, can anyone recommend some easy to understand web-sites that i can reference on this information?

I'm just a lurker, not TTC yet but...

www.babycenter.com
www.babyzone.com

Sperm can live up to 5 days.....
does that help any?

right, it can live up to 5 days in your body...so let's say, you had sex Tuesday....and O'd on Thursday. So the spermies were in there, swimming away and met the egg on Thursday. Make sense?