In the Doctor Who universe, what are the differences between Biblios, Carsus and “The Library” libraries

Question

In the List of Doctor Who planets, there are three planets that have similar libraries:

• Biblios
• Carsus
• The Library

What are the physical differences among the planets? And what are the differences in content/knowledge that can be found in each one?

Answer 1

Biblios

Biblios was a library planet which collected all the known data of the universe except for weapons.

It was curated by robot librarians.

It first appeared in the Comic War of the Words.

Library of Carsus

The Library of Carsus was the largest repository of knowledge in the universe.

It was curated by a Time Lord and friend of The Doctor, Professor Rummas.

It first appeared in the novel Spiral Scratch.

It is a very large pentagonal building on the planet of Carsus, but the planet itself is not entirely a library, unlike the other two.

The Library

The Library was simply a planet-sized library containing every book ever written, and only books. No other medium of knowledge was present there.

It was curated by robotic drones driven by CAL.

It first appears in the modern Doctor Who TV episode Silence in the Library.

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TL;DR

Biblios - Library Planet, all known data of the universe, except weapons.
Library of Carsus - Large Pentagonal-shaped Library, largest repository of knowledge in the universe.
The Library - Planet-sized Library, contains every book ever written.