CentOS 4 offers both yum and up2date to do updates of the operating system. You can use either or both of these to manage your updates.
Prior to using yum, you must import the RPM-GPG-KEY for CentOS-4 like this
rpm --import /usr/share/doc/centos-release-4/RPM-GPG-KEY
The following files are changed from the upstream RPMS. All changes are trademark and look/feel related unless otherwise noted under the specific RPM.
anaconda
anaconda-help
anaconda-product
anaconda-runtime
centos-release
desktop-backgrounds-basic
desktop-backgrounds-extra
firefox
firstboot
glade2
gnome-desktop
gnome-desktop-devel
gnome-session
httpd
httpd-devel
httpd-manual
httpd-suexec
indexhtml
initscripts
kdebase and kdebase-devel
libIDL and libIDL-devel
mod_ssl
nss
nspr
redhat-artwork
redhat-logos
redhat-release and rpmdb-redhat
rhgb
rhn-applet
seamonkey
seamonkey-chat
seamonkey-devel
seamonkey-dom-inspector
seamonkey-js-debugger
seamonkey-mail
squirrelmail
thunderbird
up2date
up2date-gnome
createrepo
sqlite
sqlite-devel
python-elementtree
python-sqlite
python-urlgrabber
yum
yum-metadata-parser
For more Information, see the CentOS-4 Documentation at CentOS.org, or the /NOTES directory on CD-1 of this distribution. The documentation is provided {and copyrighted} by Red Hat®,Inc. The CentOS Project redistributes these original works (in their unmodified form) as a reference for CentOS-4. CentOS-4 is built from publicly available, open source SRPMs.