vista window mail

on my primary desktop I use Outlook Express as my mail software. My HP laptop has Vista Windows Mail. I have a xx@sbcglobal.net adddress. I want to be able to go back and forth on either machine to check/create mail. But I am not sure what happens when I check my email on the laptop. Can I still see that same email when I use my desktop? I guess I am asking if sbcglobal.net acts the same as Yahoo or Hotmail, in that I can view/create it from any computer?