# To install the latest version of a package:
yum install <package name>

# To perform a local install:
yum localinstall <package name>

# To remove a package:
yum remove <package name>

# To search for a package:
yum search <package name>

# To find what package installs a program:
yum whatprovides </path/to/program>

# To find the dependencies of a package:
yum deplist <package name>

# To find information about a package:
yum info <package name>

# List currently enabled repositories:
yum repolist

# List packages containing a certain keyword:
yum list <package_name_or_word_to_search>
 
# To download the source RPM for a package:
yumdownloader --source <package name>

# (You have to install yumdownloader first, which is installed by the yum-utils package)