alsa versus oss

To: fedora-list@xxxxxxxxxx
Subject: alsa versus oss
From: Zoran Spasojevic <news@xxxxxxxxxxx>
Date: Wed, 22 Jun 2005 04:52:01 +0000
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How can I tell whether I am using alsa or oss?
And how can I tell my fedora to use one instead of the other?
Thanks,
Zoran