Wht's the rules on trails if theirs only room for one and it's on a hill? I was told the guy going up gets to go but the guy going down has a hard time to stop. Is there a "law" for the trail on this? This is for coming in different directions.   

I let the guy coming down go first so i have a clear shot at the hillso i don't wreck or lose control trying to go around him

Yea I mean if you are already going up or down before you see the other guy. I was told the guy up gets to go first but it's so hard to stop sometimes going down I wasn't sure. So what if you don't see eachother later when you are both on the hill?  

Well then in that case if i am going up if i can i go off the trail and go around or if i am going down and i meet some one i get off of the trail and keep going . i cross country race so i do that to pass people. i also do that when i am trail riding because i ride with a lot of 4x4s and i want to go fast so i pass them.

Im usually riding so fast that I already ran off the trail and into a tree or something   So I just stand next to my bike, nod my head and tell them im ok and take off again after they pass. LOL

On a serious note.  Every hill and every trail is different.  I always  look for a clear spot to give them room,  or look to see if they are stopping to give me room to pass.  If its a young rider, I ALWAYS give them plenty of room.    Ive never had problems on the hills, its the blind corners that seem to give me the "close calls".   I ride at Wayne National in Ohio, and they have a lot of bind corners.   Use your best judgement, and be safe.