Hey I need help with "Cameras".

I'm making a detective adventure game or whatever it's not important. But what is important is how I can "make" Cameras in the game world. When the player starts out, it will have a certain camera view port, then if he/she goes to another area and walks over a trigger it switches to another camera view port. But obviously I need to figure out how to get multiple cameras up in the game world first.

If you can point me to a doc that can give me some more information on this it would be really helpful.
Thanks,
Brent Corr