Dyson sphere

A Dyson sphere is an idea about a structure that surrounds a star, first thought up by physicist Freeman Dyson, and then used in some science fiction works. 
The idea of the Dyson sphere was the result of a thought experiment. Dyson noted that civilizations constantly increased their need for energy. He reasoned that as human civilization went on, there would come a time when it demanded more energy than the Earth could provide.
He proposed a system of structures designed to intercept and collect all energy produced by the Sun. Dyson's proposal did not detail how such a system would be constructed. His 1960 paper "Search for artificial stellar sources of infra-red radiation", in the journal "Science", was the first to present the concept of the Dyson sphere.
There are at least three types of Dyson spheres: 
A far bigger Dyson sphere would be a Birch World