EPEL is a repository maintained by Fedora Project which contains various additional packages for enterprise Linux distributions like Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL), Oracle Enterprise Linux(OEL).
EPEL can be installed on CentOS 7 as follows.
wget http://epel.mirror.net.in/epel/7/x86_64/epel-release-7-0.2.noarch.rpm
yum install epel-release-7-0.2.noarch.rpm
You can find out more about EPEL on Fedora Project wiki
Happy Installing.
