Linux Directories and Files Cheat Sheet

Just a memory dump for important files and directories.

~/.bashrc
runs on interactive login
~/.bash_aliases
runs from .bashrc (if uncommented…)
~/.emacs
Emacs settings
/etc/crontab
file that controls scheduled running of scripts
/etc/cron.d/hourly, daily, weekly, monthly
for running scripts on a scheduled basis
/etc/group
groups in the system
/etc/hosts
hard-coded hosts like in Windows.
/etc/motd
the greetings text when logging into the system
/etc/resolv.conf
DNS hosts
/etc/sudoers
users and groups that can do sudo. Edit via sudo visudo.
/etc/syslog.conf
log configuration (cron etc)
/etc/init.d/
daemon control files. To remove from startup, use sudo /etc/init.d/XYZ stop, sudo update-rc.d -f XYZ remove. To start manually: sudo /etc/init.d/XYZ start
/etc/init.d/gdm
Gnome Desktop Manager.
/etc/rcS
file run at system start. Runs the files in /etc/rcX.d depending on run level
/etc/rcX.d/
files that are run from /etc/rcS depending on run level. See The Linux Boot Process Explained
/var/log/
log files
/var/run/
lock files and run-time information
/etc/apt/sources.list
the list of URLs for apt-get for upgrading / installing packages

Also see Filesystem Hierarchy Standard.