How was the source code of the first generation computer developed?

Then you can study it carefully. When I was studying, I knew that the earliest code was written on paper tape in the 40 s and 50 s, but it was still the era of punching. The computer is a control circuit, it is not used for entertainment and office. At that time, it was mainly used in numerical calculation and other related fields. So in the circuit design, it is paper tape input, and the circuit recognizes those predetermined sequences.