I am new to linux.I am looking at some configuration notes for a CentOS, but I am configuring a Redhat machine. I am not clear:What the below commands install?  Why one might install these?  Are these applicable to a RedHat installation?    yum groupinstall  Development Libraries    yum groupinstall  Development Tools    yum groupinstall  Server Configuration ToolsNote: I started by Googling yum group install development libraries, but felt some terms might be ambiguous.
yum groupinstall Development Libraries
rhel;yum
Group install just installs some group of packages (= all packages in a group). This can be useful when you want to install gnome desktop, and instead of typing yum install gnome-session nautilus gdm <and many more> you can just run something like yum groupinstall GNOME desktop. For servers I don't see any reason to use groupinstall and don't recommend it: don't install anything you don't really need. Use yum install <package> to install something you really want.And, to check what's being installed with groupinstall use groupinfo: yum groupinfo  Development Libraries. To get list of all available groups run yum grouplist.