How did they program the very first IDE?
c
Solution
Very first c compiler was written in assembly language. Assembly language is written in binary language. And binary language is hardware language, it is directly executed by hardware.
I quote David Rabinowitz:
Please read about compiler bootstrapping and the history of compiler writing
The idea is to write a very simple compiler directly in machine code, use it to write a more sophisticated compiler, use the second one to build a third one and so on until you can have a full featured compiler.
See the complete thread here.
Problem
If C was used to program Unix, what was used to program in C? and so on and so on, ie. how did they create the very first program?