HELP! I live with 2 female cats that don't get along?

I have a cat and I recently moved back in with my parents. It's only temporary. They have a cat also. I've followed every advice I've found on the internet. My cat stays in my room and she has all her things there, but the other cat keeps standing outside the door hissing!
My sister and my mother keep saying I should just let my cat out and let them meet but I think that would be a bad idea. I don't want them to start fighting.
It's been like this for 2 months... is there anything I can do to make the introduction to my cat a positive thing? I just want the other cat to stop hissing because she is scaring my cat.

Thanks for your answers.... the very funny ones too! I like the one about placing each cat in their carrier and have them meet that way. It should be interesting.... =)
I will try it, and thanks so much for answering.

The occasional cat fight is expected in multiple cat households, because cats are territorial. However, when aggressive behavior becomes the norm, you can take steps to stop it. These are some cat training tips I use, and a few more from Friskies cat food: Identify the aggressor and victim, then separate the cats when they can鈥檛 be supervised. Give the aggressor corrective measures, and the victim rewards.
Corrective measures can include: confinement in a less attractive space; place a collar and bell on the aggressor; squirt the aggressor with a water sprayer during aggressive acts. For the victim give rewards such as free roam of the house, plus edible and affection rewards. Gradually increase the supervised interaction, rewarding good behavior and using corrective measures against cat aggression.
To help lessen the defensive posturing between housemates, take steps to make the cats smell similar to each other. Rub talcum powder on each cat or spritz cologne on your hands and when it is dry pet both cats (don鈥檛 put the cologne directly on the cat-their noses are much more sensitive than humans). You should use the same grooming tools (combs, brushes, towels, mitts) on both cats to transfer their scents to one another.

after two months the other cat is demanding to know what is on the other side of that door.
it is a good idea to keep the cat in the room at first, but you do have to let them meet.
when you are in your room let the other cat in. and watch her. as long as they dont fight, leave them alone.
mom's cat should either get along with your cat, after a few visits, or learn that your room is your cat's territory, and stay out.

safest way to do this is to put one cat (or both) in a pet carrier and let them meet face to face; if all goes well and they arent reaching out to smack each other you can let the cat out and watch them closely when they are in the same room

Cats are pretty territorial and it's possible they will never get along. I would continue to keep them away from each other or find a different place for cat to stay until you move again.

sounds like 2 ******* acting like a *****. lol damn don't humans react the same way too? lol its hilarious.

Males hate male Femails hate Femails but a boy might let boy and girl frends on land

kill your parents cat.

post a guard dog at your door

I read that if you take lemon juice or tuna juice and place it on the back of their ears they will stop the fighting/hissing and sniff each other. It's the smell that is weird. Just a dab will do. They will sniff each other behind the ears. Use the same flavor juice on both. Something about smelling the same will calm them down and get to know each other. Read that on the internet a couple weeks ago.

OR take a cloth and rub it on your cat, then let your parent's cat smell it, vice versa with their cat. Then slowly introduce them to each other.