yum commands

Pls go through it, no more doughts remain regarding yum commands:

To download and install all updates type the following command:
# yum update

List all installed packages, enter:
# rpm -qa

# yum list installed

Find out if httpd package installed or not, enter:
# rpm -qa | grep httpd*
# yum list installed httpd

To check for and update httpd package, enter:
# yum update httpd

Search httpd and all matching perl packages, enter:
# yum list {package-name}
# yum list {regex}
# yum list httpd
# yum list perl*

Remove package called httpd, enter:
# yum remove {package-name-1} {package-name-2}
# yum remove httpd

Display the list of available packages
# yum list all

Display list of group software

Type the following command:
# yum grouplist

You can easily find out what RPM package provides the file. For example find out what provides the /etc/passwd file:
# yum whatprovides /etc/passwd

Task: Display the list of available packages

# yum list all
Task: Display list of group software

Type the following command:
# yum grouplist

If still having any doughts feel free to ask us, i will do my best to resolve ur problem.