The culture of Colu has changed over the years. Exploration of Coluan culture has been prominent in Legion of Super-Heroes and L.E.G.I.O.N.
On New Earth, Colu was known to its inhabitants as Yod. The most significant moment in the planet's history was when Vril Dox, the adopted son of Brainiac liberated the planet from the Computer Tyrants. Its populace hunger for knowledge and the merging of organics and cybernetics is common. Robots play an important part in security of the planet. Colu's intelligence has stagnated over a period of 1000 years caused by the actions of Brainiac, Vril Dox and Brainiac 5 (of Earth 247). This is due to a reliance on theoretical research rather than practical experimentation.
On Earth- 247 the people connect in sleep through a network to communicate.
On Earth Prime we discover that Colu has found a way to combat its over-population crisis. It has shrunk itself using the same technology Brainiac used to shrink Kandor and his other bottle cities. It is known to the universe as 'The Bottle Planet of Colu'. During this time Colu's population is drained of its intelligence. An act Brainiac 5 considers genocide.
In Other Media
In the Legion of Super-Heroes Animated Series Colu was a completely robotic species that shared knowledge once a year during the 'alignment'. They all connect as part of a hive mind which Brainiac 5 has taken himself out of. In the final story of the series 'Dark Victory', Brainiac 5 uses the technology of Brainiac 1 to turn the whole planet into binary data. He used its inhabitants to make his body bigger as they all connected into one superstructure.