CAT command

cat /var/log/yum.log
cat /var/log/yum.log | grep mysql = mysql install and update dates
cat /proc/meminfo = prints memory info
cat /proc/cpuinfo = prints cpu info
cat /var/log/manylogs/mylogonly.log = prints output of a file
cat /selinux/enforce = current status of selinux
cat /etc/shells = lists all installed shells on the os
cat /etc/inittab = info about run levels
cat filename | sort = sorting output in alphabetical order
cat /etc/x11/xorg.conf = monitor info
cat filename1 filename2>filename3 = merges the files
cat /etc/fstab = list of all devices
cat /etc/filesystems = of file systems
cat /var/log/messages | grep -F ntpd =