Nagios Plugins web site taken over by nagios

hymie! writes: Holger Weiß , formerly of nagios-plugins.org, announced that "Yesterday, the DNS records [of nagios-plugins.org] were modified to point to web space controlled by Nagios Enterprises instead. This change was done without prior notice. To make things worse, large parts of our web site were copied and are now served (with slight modifications) by . Again, this was done without contacting us, and without our permission. This means we cannot use the name 'Nagios Plugins' any longer." Announcement here, discussion here

great

[Megane]

So what's a nagios and what does this mean?