How long ago your Linux system has been installed?

Do you need to know when your Linux has been installed?
here you have one way
i used tune2fs on Arch linux
basically command is”
sudo tune2fs -l /dev/YOURPARTITION | grep ‘Filesystem created:’
This useful command checking file system data creation and consequently, operating system installation date (unless you are checking  an empty partition:-)
In my case, partition is /dev/sda6, where i have installed Arch linux almost one year ago

If you don’t remember your partition , you can execute sudo fdisk-l , partition is obviously “Linux filesystem”