problem with browser

[inaction]

I use $_POST to send all the information to other pages using forms but when I get to the other pages and try to find mistakes with my programming i find:

When I refresh the window the action from the previous page happens again i.e. if I am emailing something everytime I refresh that page I email out another email.

Is there anything I can do to correct this problem with php or anyother programming language thanks for the help

The problem is that when you refresh the browser it seems to hold the same $_POST values

[inaction]

Also another solution might be to detach the refresh button at the top of the page but I am going to make this same page a refreshable page every 30 seconds or so. Therefore I want my code to refresh the page