why does my adrino say this at the top of a blank page every time i open the program up?

Because it is your first sketch ("a") today, August 13th

thank you! i have just got this unit, and i am so confused right now, trying to figure it out, thanks so much for your reply.

That's the default filename that it puts with the new file you just created. If you type a program and then save-as, the name up there will change to whatever you name the file.