How can we use in MacOs X Systems Windows based Operating Systems?

We have 2 ways;1. We can use Mac BootCamp Assistant to install Windows. But i dont prefer this way, thats why i wont explain that way deeply.2.Using a program to install a virtual machines such as VMware Fusion and ParallelDesktops. You can choice one of them to install the system. I have preferred VMware Fusion, i downloaded and installed this program on my Mac. Then we create a virtual machine for Windows Xp, for this system we adjust the hardware configuration such as  HDD size, RAM size and the other configuration. When there is not any kind of error, then we are installing the Windows XP in this Virtual Machine. We are installing the system ordinarily, and then the system will be ready after some simple configuration such as network and the other simple configuration. Its very simple to copy or paste folders and files with the systems one another by this way.