Default File location and descriptions for Linux (CentOS server), it will help to understand the Linux CentOS.
/etc/hosts # Known IP number/name bindings
/etc/fstab # Define mount points & filesystems
/etc/smb.conf # Config Samba server
/etc/exports # List of nfs exported directories
/etc/cram-md5.pwd # Imap & pop3 access: username password
/etc/dhcpd.conf # Configure dhcpd server (bootp)
/etc/inetd.conf # Configure servers (telnet, tftp, etc)
/etc/bashrc # Global functions and aliases
/etc/lilo.conf # Edit for boot setup, then run lilo
/etc/localtime # Link into a /usr/share/zoneinfo file
/etc/named.conf # Configuation for named DNS (bind)
/etc/resolv.conf # IP names and config for DNS
/etc/securetty # Terminals that are allowed to be root
/etc/DIR_COLORS # Colors used by color ls
/etc/modprobe.conf # Configure module loader
/etc/printcap # One entry per printer
/etc/profile # Global environment and startup
/etc/profile.d/*.sh # Modular global environ additions
/etc/ppp/options # Contains lock for ppp (Remove lock!)
/etc/ppp/ip-up.local # Things to do after connecting
/etc/ppp/pap-secrets # Username-password entries
/etc/ppp/resolv.conf # Created by ppp with usepeerdns option
/etc/pcmcia/config.opts # Used to exclude IRQ 12 for PS/2 mouse
/etc/pcmcia/network.opts # Configure and start pcmcia ethernet
/etc/securetty # List terminals allowed to login as root
/etc/sysconfig/pcmcia # Use this to turn on pcmcia
/etc/sysconfig/network # Start networking, set def gateway
/etc/sysconfig/network-scripts # ifcfg-xxx files for each interface
/etc/sysconfig/clock # Vars used in rc.sysinit to set the clock
/etc/sysctl.conf # Kernel settings for /proc/sys boot
/etc/rc.d/init.d # Start/stop scripts for system services
/etc/rc.d/rc.sysinit # Boot time configuration script
/etc/X11/XF86Config # Configuration for XFree86
/etc/X11/XF86Config-4 # New Configuration for XFree86 4.x
/etc/X11/fs/config # Configuration for xfs font server
/etc/X11/xdm/Xservers # List of servers and displays for xdm
