Civilization IV modding?

I am using Civilization IV beyond the sword, and I was looking at some pages on the internet about civilization stuff. I came across civilizations other people have made that you can download. I think they were called "mods." How do I get these civilizations into my game?Civilization IV modding?
Ah mods. Mods stand for modules, and are add-ons created by other people to add, change, or remove certain elements from your game. Mods are available for a wide array of games (e.g. Civilization IV, Fallout 3, Dragon Age: Origins, Dead Rising 2, Oblivion, etcetera), and most games these days has built in mod support. You can Google Civilization IV mods if you want, or you can go to http://www.civfanatics.com/civ4/download鈥?/a> - as is quite a good website to start at if you don't know what a mod is.