system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] What is the relationship between each of the Lantern Corps?

I know Green's are the "protectors of the Galaxy" or something like that, and the Sinestro Corps like to be mean and evil and stuff - but what do they other Corps do for the other colours? Do they do the same stuff, cause trouble - are they all on call with each other in case they need help. I saw a scan where Hal Jordan was asking Superman if he should call the Red Lanterns, are they benevolent or do they just like to smash things?
gpt
The Red Lanterns were created as a form of primal justice for the galaxy.  They use the rage in their hearts to kill those who would do harm to the innocent.  No due process needed.  Their leader, Atrocitus harbors great hatred for the Guardians of the Universe for the "glitch" that caused their Manunters to wipe out his family and species from his homeworld. Due to this hatred, the Green Lantern Corps is seen as an enemy as well.

The Indigo Tribe was created by Abin Sur and Notromo after discovering the Indigo Light.  The tribe was created to combat the Blackest Night and even was meant to stop the Guardians.  All the members of the tribe were test subjects to see how the Indigo Light can be used.   The worst scum of the universe were subjected to be a part of the tribe so they may know what compassion is.  They consider themselves allies of the Green Lantern Corps as they assisted in fending off the Blackest Night.

The Blue Lantern Corps were created by the Guardians Sayd and Ganthet.  They were meant to be joined along with Green Lanterns since the blue light of Hope can overcharge a Green Lantern's ring to be incredibly powerful as the power of Will from a Green Lantern ring unlocks a Blue Lantern's ring to be able to use constructs.  With no Will present, Blue Lantern members can only use the ring for flight and protection.

The Star Sapphires' relationship with the Green Lantern Corps is someone strained and political.  They wish to bathe the galaxy in Love (without choice) but the Guardians do not believe it should be forced upon everyone in the galaxy.  However the leaders of the Sapphires, the Zamarons are cousins of the Guardians and try to maintain somewhat of a peace between the Sapphires and the Green Lanterns although both sides would like to be rid of the other.