Question: More than one way to perform the function, do I have to patent them all? How?
Question Detail: I have developed a system to do a certain function. But later on I figured out there are more than one way to alter the system to do the same function, so if I patent the system is it possible for someone else to modify it then patent it? How well would a patent protect my idea in that scenario?

ANSWER: Yes. Others may invent a system that is different from your system but perform the same function. If you are trying to prevent others from performing the same function, you can try to patent a method. And you can also try to patent different variations of your system.