i have been watching a lot of videos on gameplay because i cant wait to get it and i love it when a female is singing a males vocals because it sounds cool and i have noticed that on a lot of them it says fc in brackets and i heard someone say somewhere that it would be better if they fced it and that got me thinking so what does it actually mean

FC = Full Combo = Got 100% of notes hit without breaking combo

100% = Got 100% of notes, with 1 or more overstrums

what is overstums and what does it mean if it says fbfc in brackets

When someone overstrums they haven't missed any notes but they have messed up their streak by strumming when there isn't a note.

If you have 100% in a song and you have one last note if you strum that twice you will hit the note but lose your combo, therefore missing out on making it a successful FC.

I've never seen FBFC before so I don't know about that one.