Okay first of all, don't post misleading titles. You will not lose your entire computer simply because you don't have information on the new patch. Your computer will do just fine without it.
The new patch is an update for FH. It contains new maps and some glitch fixes.
Everyone will need to download it eventually. You get access to new (and fun) maps wings, items and a few other goodies, so it is worth a download as soon as possible. I am afraid I can't give any information for a mac computer though...