Dieudonne

submodule of free module (not necessarily over PID)

C[x,y]

Noetherian + finitely generated implies that tensor preserves completion

Étale algebra arise from base change

R-linear category

Additive category

morphism of complexes or complexes being

Homotopic to zero

Derived category

Injective modules

RF appears!

What are hom in D(A)?

Functors on D(A)?

"total derived functors"?

Why the system of quasi iso is richer than the cohomology group?