How was the first OS and dandy games created?

Question

Programming

Tell me, is windows written in C?
but how was C itself written when there was no Windows yet?
and how games were written then, how could an oblong green piece contain such a miracle of the game, where was the logic and bots, where was everything stored on this board?
and why did many cartridges have different shapes?

Answer 1

Why not read Kernighan & Richie , at least the preface.
The cartridges had different shapes, because their creators did not have enough imagination for different contents.