The Real (Hi)Story of Christmas

I'm so curious on history of Christmas.. why Christmas is in December?

And why it's on the 25th?

Is this the accurate date and month? And why people relate Christmas to winter/snowy thing?

I found this link: http://www.history.com/minisites/christmas
And the title of it is The Real Story of Christmas.

It's quite an interesting reading, (for me) for just to know the history of it. Not misleading or doubting my faith or whatsoever... Just a curiosity.. thats all.

(fyi I'm not reading it while I'm having the KFC, I never eat in front of computer bcos I will have loads of germs attach to my computer.... wekkk ;p ---> GERMS FREAK)