Linux etc

/etc/*-release

Information about your linux dstro.

# tested on: Archlinux, FreeBSD
distro="$(cat /etc/*-release | grep ^NAME)"
distro="${distro//NAME=\"/}"
distro="${distro//\"/}"

/etc/rc /etc/rc.d /etc/rc1.d

Symbolic links to startup scripts contained in init.d. rc1.d rc2.d rc3.d etc. correspond to different run levels.

The Linux filesystem is designed in a fragmented way so that you can have some parts, or the entire filsystem shared across a network on a remote machine, OR be able to function off a read-only device such as a CDrom.

User Info:

/etc/hosts

A list of computers that can be contacted using the network without a domain name service. If the hostname of a different computer isn't being resolved, you can add it to /etc/hosts

/etc/passwd

User Database. Usernames, Real Names, Home directory + other info. see man passwd

/etc/group

Lists groups of users

/etc/shadow

encrypted file that holds user passwords

Startup Info:

/etc/fstab

Lists filesystems mounted automatically on startup. Can be user modified.

/etc/inittab

Config file for init

/etc/mtab

Currently mounted filesystems