the front (fore waters) is basically the bag in front of the baby's head.. closest to where they come out.. and this is the main part that stops infection etc reaching bubs..
when these go, it should gush and it's rare to get a leak - but they can't usually repair themselves
the back (hind waters) is the rest surronding baby and sometimes they can repair themselves, depending how bad the rupture is.. bubs's head can also block this leak or these can sometimes leak when bubs is engaging..
they both come out the same place - and usually come out at the same time.. just one is to protect one part of baby and the other is to protect the other part...
hope that helps..
xxxx