Hello Cindy,
'For the record' means for the sake of strict factual accuracy.
It is used many times by reporters in speeches to announce that the facts will be known for the public.
" I would like to mention -for the record- that the profits this year exceeded those of last year by 30% percent."
It is kind of an announcement for public knowledge that reflects accurate and precise facts.
It also indicates that the facts the person is stating are clear and that he requires the attention of the listeners, because it is important and he wants them to remember.
" Just for the record, I have never met him in real , whatever the media is saying."