Canonical Decomposition
I find this slide from Christoph Freudenthaler very useful.

Canonical decomposition visualized by Christoph Freudenthaler
Planted:
by L Ma;
Dynamic Backlinks to
cards/math/canonical-decomposition
:L Ma (2019). 'Canonical Decomposition', Datumorphism, 06 April. Available at: https://datumorphism.leima.is/cards/math/canonical-decomposition/.