Sorry guys, I forget some of you are too young to have watched some of the EPIC Episodes of "Star Trek - The next Generation", some fifteen years ago.
Or maybe that show never ran in India. Anyway, If you get the show on video , it is worth watching.
Borg were these half human half Machines with a collective mind and they went along snatching humans to join them.
That line is the most famous line of the show, " Resistence is futile, you will be assimilated".
That is the context here. Try to Google it.