Survival of our species/Preserving knowledge

Think of all the knowledge we have gained since the stone-age - all our writing systems, mathematics, agriculture, medicine, science, engineering and so on. It needs to be pretty well looked after, and able to survive huge catastrophes. If there was a large asteroid strike with 95% of the human population wiped out and the environment degraded for decades, the last thing the remaining people need is to be plunged back into another stone age.