Installing ROOT
Before you begin, please go through the web page: root.cern/install.
Operating System
For all data acquisition and analysis work, please use Linux, not Windows. It is preferable to install Linux as a dual boot and not as Windows Subsystem for Linux (WSL). If you are using a distribution of Linux other than Ubuntu, the installation procedure could be slightly different.
To find out your Linux version type the following command from a terminal:
$ cat /etc/os-release
Installing from Pre-Compiled Binary
In the ROOT Lesson 1 video (created in 2022) I demonstrated installation on Ubuntu-20 using a pre-installed binary. With newer versions of Ubuntu and ROOT, you can follow a similar procedure, provided the required pre-installed binary for your Ubuntu version is available.
From root.cern/install/all_releases select the latest release of ROOT, navigate to its binary distribution page and click the .tar.gz file to download it. At the time of writing (Feb 2026) this would be root_v6.38.00.Linux-ubuntu25.10-x86_64-gcc15.2.tar.gz (for Ubuntu 25) to be found in the list of binary distributions.
You can follow the ROOT Lesson 1 video to complete the installation. Bear in mind that the video is old - there would be some differences in the pre-requisites etc.
Dependencies
First you have to take care of installing packages that ROOT needs. You can see the full list here. The easy way to install all dependencies is to type the following commands on a terminal:
$ sudo apt install binutils cmake dpkg-dev g++ gcc libssl-dev git libx11-dev
$ sudo apt install libxext-dev libxft-dev libxpm-dev python3 libtbb-dev
$ sudo apt install libvdt-dev libgif-dev
For your convenience, I have split the requirements into three commands. Alternatively you can type a single command split over two lines using the backslash line continuation character like this:
$ sudo apt install binutils cmake dpkg-dev g++ gcc libssl-dev git libx11-dev \
libxext-dev libxft-dev libxpm-dev python3 libtbb-dev libvdt-dev libgif-dev
Install ROOT
Detailed instructions are in this link. The easy way is to type the following commands on a terminal:
$ wget https://root.cern/download/root_v6.40.00-rc1.Linux-ubuntu26.04-x86_64-gcc15.2.tar.gz
$ tar -xzvf root_v6.40.00-rc1.Linux-ubuntu26.04-x86_64-gcc15.2.tar.gz
$ source root/bin/thisroot.sh
The command source root/bin/thisroot.sh should be added to your .profile hidden file so that you dont have to type it after every login. This command allows you to run ROOT from anywhere.
Running ROOT
If you added the command source root/bin/thisroot.sh to your .profile hidden file, you should logout and login again (or reboot). Once the command source root/bin/thisroot.sh is active, you can start ROOT from any directory just by typing root.
Installing using the SNAP package manager
Using a package manager like SNAP is certainly easier because you don't have to worry about dependencied and it also automatically takes care of updating when a newer version of ROOT becomes available. When installed this way, the necessary paths are automatically setup. To install using SNAP, type from a terminal:
$ sudo snap install root-framework
Other Package Managers
If SNAP does not work for you, please look at other package managers to see if you can find a suitable package.