Get the OS Installed date

Hi,

How to get OS installed date in Linux using terminal command?

Thanks is advance

In short: you can't (at least not with any default command)
Long answer: you can't, unless you know where to find the distributions install logs (if any were made), and you've kept them.

On Fedora, Redhat, and Centos you can retrieve the install date from the creation date of /root/install.log.

I'll take a guess that /var/log/YaST2/y2start.log is the equiv for openSUSE and SUSE Enterprise.