If you are getting some errors while installing the Steam client in Ubuntu 13.04 or Debian 7 from GUI (Ubuntu Software Cneter, etc.), you can resort to the terminal as shown below. In this brief guide we will see the commands needed for the proper installation of the Steam client under Ubuntu, Linux Mint and Debian systems.

1. Installation For Ubuntu 13.04 (or older)

Open the terminal and run the following commands:

sudo apt-get install curl jockey-common
cd /tmp
wget http://goo.gl/KY0N3B -O steam.deb
sudo dpkg -i steam.deb
A window will pop-up, click the "Start Steam" button, then accept the license agreement:

Finally, wait until the installer completes the installation process.

2. Installation for Debian 7 "Wheezy" (or older)

Before installing the Steam client in Debian, please run these commands if you are running under a 64-bit system:

sudo dpkg --add-architecture i386 
sudo apt-get update

Start now the installation with these commands:

cd /tmp 
wget http://goo.gl/fHS0p7 -O steam-debian_1.0.0.39-10-2_all.deb 
sudo dpkg -i steam-debian_1.0.0.39-10-2_all.deb 
sudo sh /usr/lib/steam/steam-debian-depends.sh

That's it!

Note: Debian users can obtain the latest deb package of Steam from here.