Although it is technically possible and even feasible for the entire population of the Terran Sphere to live in a single (albeit large) system using methods like planetary disassembly to construct exremely large habitat clusters, such a high population density would lead to highened ideological tensions, material and energy prices, and other significant drawbacks.
This, along with the relatively low cost of jump travel once a jump gate link has been established, the relative abundance of easily terraformed worlds, the large amount of space and resources most inhabitants of the Terran Sphere expect, and a wish to get away from established orders and found a new community, has led to an explosion of colonisation efforts almost directly after the enlightenment.
Colonisation efforts can be devided into two distinct catagories: independent and dependent. Dependent colonies are founded with the intent of expanding the sphere of influence of the founding nation, providing the homeworld with a new population center, military base and source of trade. Dependent colonies usually have a jump gate link connecting them to the rest of the nation even before the first permanent settlers arrive.
Independent colonies, on the other hand, are founded with the intent of getting away from the founding nation in order to get away from taxes, persecution, high population densities, war or annexation, or occasionally out of sheer pioneer spirit. Independent colonies are usually founded by a colonisation fleet setting off into uncharted space until it comes across a suitable system. A small but considerable amount of these efforts fail.
Most worlds of the Core are independent or a blend between independent and dependent, being sponsored by the Solar Union to accept those who felt uncomfortable with the Union's rule and trading to a limited extent, but not expected to pay taxes or submit to the Solar Union directly.
Other pages about colonisation:
* Mining colony
* Successor world
