What is difference between Axioms, Postulates and Theorems?

Axioms and Postulates

Just like

2 + 2 = 4,

2 comes after 1……

Axioms or postulates are universal truths.

They cannot be proved.

Usually, postulates are used for universal truths in geometry, and axioms are used everywhere. Though, both mean the same thing

Theorems

Theorem are statements which can be proved.

Example: Prove Pythagoras Theorem