How does Boot Camp Assistant facilitate Windows to be installed on a Mac?
Boot Camp Assistant helps you create a Windows partition that will "house" the Windows installation.  This partition will reside separate from Mac OS X and once Windows has been installed, you'll be able to boot your Mac into Mac OS X or Windows.

Don't I need Windows drivers?
Yes you do, you will find these drivers on the Mac OS X installation disc that came with your Mac and/or via a Boot Camp Assistant update from Apple.

Can you explain it a high-level?
The Boot Camp Assistant utility helps the person performing the Windows installation create a partition.  It then restarts your Mac after you have inserted the Windows installation disc. You then follow the steps to install Windows.  Finally, install Mac-specific drivers to allow you to optimally use Windows on your Mac.

So the three key steps are:

1. Run Boot Camp Assistant
2. Install Windows
3. Install the Boot Camp drivers on the Windows partition

What are the requirements?

• An Intel-based Mac
• A USB keyboard and mouse, or for Mac portables, a built-in keyboard and trackpad
• The latest version of Mac OS X - (refer to Software Update)
• At least 10 GB of free space on an internal hard drive
• A built-in optical disc drive or a compatible external optical drive

Key points about the Windows installation disk
A full Windows installation disc is required, an upgrade version is not supported.
Windows 32-bit version
Windows 64-bit is supported on the Mac Pro and MacBook Pro early 2008 or later

By enabling the installation of Windows on a Mac, Apple has made it that much easier for users to make the Switch To A Mac.  Users can have a single system that can run both Mac OS X and Windows thereby allowing users to use the operating system they need at any given time.