Space colonization, also called Space settlement refers to the idea/possibility/necessity of building artificial environments in space outside Earth to be inhabited permanently by humans. Because humans cannot live self-sufficiently, other species would have to be able to live in the habitats as well.
There are besically two types of space habitats:
- Habitats on a planet, either fully isolated from the natural environment or by changing this environment itself to make it more life-friendly, a process called terraforming.
- Habitats in space: space stations.
There is a wiki dealing with space colonization at http://www.luf.org/bin/view/Main/WelcomeGuest.