Hi everybody!
Welcome to an LHC@home tutorial. This one is dedicated for Linux users. If you use Windows or Mac you will find similar ones soon (at website).
My name is Karolina. I am a student in the IT Department at CERN.
Today, I would like to show how you can support scientists in their quest for a better understanding of our universe just by offering the spare power of your processor. 
For this purpose we are going to use BOINC, which is a program that uses your computer (when idle) to solve scientific problems. BOINC allows you to access many different volunteering cloud computing projects from all around the world, some of them help scientists working at Large Hadron Collider. At the end of this tutorial you will be able to run computational tasks for one of the LHC projects.

To begin we go to LHC@home website and choose the JOIN US tab. First thing we are told to do is to install the BOINC program. There are several ways to do this, but I recommend to install BOINC as a system package. You open your terminal and, for debian, type "sudo apt-get install boinc". Note that you need to have the superuser privilege to do so. This command installs both the boinc_client which is the program required for all BOINC project and the boinc-manager which is a graphical user interface to manage BOINC.
Depending on which Linux distribution you use, change the installation command accordingly.  For example for Fedora/CentOS/Scientific Linux use, "sudo yum install BOINC".

If your distribution of Linux doesn't provide a package for BOINC or you are not sure if it is the most recent one, click on the button below (install BOINC), download .sh file, add executable permission and run it. If you use testing distributions you might have to install BOINC from source, which you can find on this website (click on "distribution-specific package" link).

Now you should be able to run the boinc client and the boincmgr,  but you are not yet running a  project. To change that, go to the LHC@home website where under the "Projects" tab you find the list of projects related to CERN. There you can read more about purposes of each project and you can choose the one that interests you most. Then go to BOINC site of the project, choose "log in", create an account and fill a form. With BOINC you can run several projects at the same time, so I encourage you to sign-up for a few of them. 

By now you should have BOINC installed on your computer and be a member of at least one project.
Now you need to check if your project needs any additional programs. For most of the LHC@home projects you need VirtualBox. As we did before, we are using system package so we are just typing "sudo apt-get install virtualbox" or yum depending on your distribution. To run VirtualBox you need the virtualization technology enabled on your computer (you might need to change it in your BIOS menu). Consult on VirtualBox webpage if you have any issues (show the link).

When you have VirtualBox installed you have all the necessary tools to run projects under BOINC.
The one last step is to connect your project account and BOINC, which you can do using command "sudo boinc --attach_project" with two arguments: the URL of the project (the one seen on the BOINC-site) and your account key that you can find on the project site after you log in to your account.

Voila, BOINC should be now up and running. If you open the BOINC manager you should see tasks related to the project that you chose. From within the boinc-manager you can also add new projects and manage the ones you are in. You can, for example, limit the CPU, memory, disk or network usage according to your preferences. Many options can be also changed on the project's webpage under your account. 

Thank you for following this tutorial and I hope BOINC is now up and running for you.

If you want to know more about different BOINC options go to webpage https://boinc.berkeley.edu/, where you should find the information you need. We will also be very happy to assist you on the project forum (show it).