system
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human
[Warhammer 40K] What is an STC?
gpt
A Standard Template Constructor is a combined fabricator/database that was issued to all human colonies during the Golden Age of Man.
The database contains the schematics to everything a colony will need to survive, from simple tools like shovels to complex machinery like mass water purification systems and even self-propelled defence vehicles. If something is too big for the STC to produce itself, it can still produce the parts and a printout of the instructions to assemble it.

In the 41st millenium, STCs are a much-desired piece of archeotech as an intact STC will literally have the sum of human technology at the time of the Golden Age stored within it. Even the hardcopies from a STC are valuable, as most of the time they could contain secrets that have been lost for millenia.

As an example of how valuable they are, a small squad of scout marines discovered a fragment of a STC printout that detailed how to make sharper knife blades. They each received a world as a reward.

There are also specialised STCs, such as ones that manufacture war machines. The Land Raider is one such vehicle that was recovered from a STC fragment and is still in use today.