The human species is destined to exploration. Our entire history revolves around the discovery of new destinations and knowledge. Unfortunately, we are also a species that is remarkably proficient in destroying our environment. The Earth's population is growing at an exponential rate and will most likely become incapable of sustaining our needs. We are running out of precious farmland and natural resources. Some day in the future it may be necessary to seek habitation elsewhere.

Building colonies on the Moon or Mars may be a possibility. Living in constructed closed environments is really only a short-term solution. Humans have not been proven capable of living in a closed environment for an extended period of time. Isolation and confinement have long been used as a form of punishment to humans. If we want to live outside the Earth, we need to somehow transform an entire planet (possibly Mars) into an environment suitable for us. This is where Terraforming comes in.