How i can now the user's browser?

[foxpro]

I need help.

I need to show a message in the netscape, modzilla and firefox browser.
This just to stop the navigation in my web page with this program (to my security.)

If you now the answer, tell meeeeeeee.

(Excuse me for my english, normalmente escribo en español)

[Twey]

Español:
Lo siento, pero no te entiendo.
Un mensaje en el pagina, o un pequeña ventana?

Intentes:
window.alert("Mi mensaje");

Es que desea?

English:
I'm sorry, but I don't understand you.
A message on the page, or a small window?

Try:
window.alert("My message");
Is this what you want?

(Si, mi español es terrible tambien :p)