Installing Steam in Ubuntu

I am currently using Ubuntu 14.10. Steam is showing up in the Ubuntu Software Center, but when I click on it it says:

Not found
^{There isn't a software package called "steam" in your current software sources.}

Is there a fix for this? Am I the only one having this problem?

First Update the system. Then try with commandline as follows:

sudo apt-get update && sudo apt-get install steam

Steam can be install as a flatpak package in all currently supported versions of Ubuntu. Open the terminal and type:

sudo add-apt-repository ppa:alexlarsson/flatpak # required in 16.04 only, not in later releases
sudo apt update 
sudo apt install flatpak
sudo flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
flatpak install flathub com.valvesoftware.Steam

Steam can be launched by clicking on its icon in the Dash or launched from the terminal with the following command:

flatpak run com.valvesoftware.Steam 

Many games require an online purchase, but some popular games, such as Team Fortress 2, are free to play. When searching in the store, be sure to narrow results by the SteamOS/Linux operating system. Not all Linux games are compatible with your system, so make sure you check the requirements before purchasing games.

The steam package is part of the "multiverse" repository for Ubuntu versios 14.04 onwards, but only for 32 bit versions of Ubuntu. If you want the 64-bit Steam package, you need to add the Steam repository to your sources.

32-bit Ubuntu

• enable the "multiverse" repository
• run sudo apt-get update
• Install steam using either apt-get or the Software Center.

64-bit Ubuntu

• add the following line to /etc/apt/sources.list:

  deb http://repo.steampowered.com/steam/ precise steam

• run sudo apt-get update && sudo apt-get install steam-launcher

or

• install the .deb manually from the official site.