Covariant and Contravariant Coordinates

Why is it interesting?

Covariant and contravariant coordinates are commonly used in special relativity.

Layman

Explanations in this section should contain no formulas, but instead colloquial things like you would hear them during a coffee break or at a cocktail party.

Student

Researcher

The motto in this section is: the higher the level of abstraction, the better.
Common Question 1
Common Question 2

Examples

Example1
Example2:

History