Ok from what I gather yumex and add/remove software are actually graphical interfaces to yum. when I open yumex or add remove software it will populate with a bunch of programs which it gives me the option of downloading (btw the download never seems to work it just hangs or has too many dependency issues but that is for another thread).

So what is exactly are these front end programs doing when they open? what is the equivilant yum command/s that would give me the option to install these programs from the command line? I don't think its yum update -y cause that only looks for updates to exsisting programs right? and the graphical interfaces are showing new programs when they open I think...help a newbie out...btw...just for those wondering centos is great I am leaning with this and fed 6 and it just works so much better imop...

The Fedora docs cover using yum on the command-line:

http://fedora.redhat.com/docs/yum/en/

As these explain, each operation starts with downloading the latest package metadata to the local system (unless you run in cache-only mode), and then looking at the relevant information in the downloaded data.

Just in case it isn't clear, I'll add that IIRC both the yum command-line application and the graphical tools actually use functions in a common set of program libraries to work with the data and packages, so I don't think that yumex literally runs a specific yum command.

thanks I am still confused though...I did a yum update -y and it says there are no packages for update/obsolition. Then I run yumex and it starts populating the install tab with lots of programs...I am about to read the doc you posted but for now I just wanted to know what yum command would show me all these programs that I can download in the same way that the graphical interfaces do...(maybe the command doesn't exsist in yum?).

The "yum update" command only lists the installed packages that require updates. The yumex interface probably shows all of the packages that you could add to your system. To see uninstalled packages, either search for what you want (the document explains how), or use the "list" options of yum.

I tend to use the Web site if I'm looking for something that isn't in Core, and I'm not sure of the specifics:

http://fedoraproject.org/extras/6/i386/repodata/