Useful and Basic Commands and Shortcuts For Ubuntu Beginners

One of my friends asked me to list useful commands and shortcuts for him to use in his ubuntu distro. I listed some pretty useful ones and am also sharing them over here.

Basic Commands

Alt + F1: Opens application menu.
Alt + F2: Opens run command(something similar to run command in windows)
Ctrl +Alt + FN: Switch to TTYN terminals
Ctrl +Alt + F7: Switch to X Display
mkdir <dir_name>: Create a directory
cd $HOME: Set the current path as your home directory
cd /: Set the current path as root filesystem

Privileged commands: Note that most of these commands require you to have sudoers privilege which is specified in /etc/sudoers file.

sudo su: Run the shell as root user.
sudo su user: Run the shell as the user specified
sudo command: Run the specified command with root privilege
gksudo command: Run the specified command as graphical root mode.(used for graphical programs)
passwd: Change your password

Basic Network Commands

ifconfig: Displays information about network. Also, ifconfig interface would give information about the specified interface.
iwconfig: Displays information about wireless network
ping host_or_IP: Pings to check if the specified host or IP is online or not. Also useful for knowing if you are connected to some other network eg. internet.
host ip_addr: Displays hostname for specified IP address by querying nameservers specified in /etc/resolv.conf
ifup interface: Bring the specified network up.
ifdown interface: Bring the specified network down.
ssh user@hostname -p PORTNO: Establish SSh connection to specified host and port number and login as specified user.

Commands For Package Management: These commands require root privilege so either escalate privilege to root by sudo su command or precede each commands with sudo.

apt-get install package1 package2 .. packageN: Download and install the package(s) specified.
apt-get install -d package: Just download the packages(no installation)
apt-get update: Update packages information.
apt-get dist-upgrade: Perform distro version upgrade.
do-release-upgrade: Perform distro version upgrade.
apt-get remove package: Remove the specified package(s).
apt-get -f install: Fix packages problem.
dpkg --configure -a: Fix broken packages.

Other/Misc. Commands

id: Displays user and group IDs for current user.
uname -a: Displays all kernel information
gedit: Open text editor
nautilus: Open nautilus file manager
gksudo nautilus: Open root nautilus file manager
lsb_release -a: Get information about installed ubuntu version

These are some of the commands that has come in my mind as of now. I might update this list when some other commands come into my mind. By the way, TAB is very useful in terminal as it allows auto-completion and suggestion of commands and files in ubuntu. What this means is if you type do- and then press TAB, it will auto complete the command to do-release-upgrade thus saving some important time. Also be sure to share the useful commands in the comment section below.