science is a rigorous, systematic goal to build and organize knowledge

ultimately, the purpose of science is to understand things

science is classified into branches, but as you can predict, sorting all knowledge into different categories is hard

formal sciences

formal sciences study abstract logical things described by formal systems
for example, logic, mathematics, computer science, and game theory
see formal sciences

natural sciences

natural sciences study the knowledge from observing the physical world
for example, biology, chemistry and physics
see natural sciences

humanities

humanities study human society and culture
for example, philosophy, religion, and fine art
see guide to humanities

social sciences

see guide to social sciences