How to check if I got some package installed?

To: fedora-list <fedora-list@xxxxxxxxxx>
Subject: How to check if I got some package installed?
From: Leandro Melo <ltcmelo@xxxxxxxxx>
Date: Wed, 9 Mar 2005 20:14:05 -0300
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Reply-to: Leandro Melo <ltcmelo@xxxxxxxxx>, For users of Fedora Core releases <fedora-list@xxxxxxxxxx>

Hi.
How to check if I got some package installed?

-- 
Leandro

Follow-Ups:
- Re: How to check if I got some package installed?
  - From: Scot L. Harris
- Re: How to check if I got some package installed?
  - From: Robert P. J. Day