Hopper both invented the concept of compiler and wrote the 1st one. No. A_0 was a simple linker in 2016 parlance, not a compiler. In Hopper's own descri

Hopper both invented the concept of compiler and wrote the 1st one. No. A_0 was a simple linker in 2016 parlance, not a compiler. In Hopper's own description: "All I had to do was to write down a set of call numbers, let the computer find them on the tape, bring them over and do the additions. This was the first compiler" (cited from [1]). Here "find them on the tape" refers to her habit of collecting subroutines over the years and put them on tape. Each routine was given a call number, so that it the machine could find it on the tape. I'm happy to believe that she created the first linker, although I have never looked into the history of linking and linkers. Plankalkül was [...] before general purpose programmable computers (ENIAC) were built so irrelevant. The first general purpose computer was Zuse's Z3, at least in some understanding of this concept [2]. [1] C. Marx, Grace Hopper: The First Woman to Program the First Computer in the United States. [2] R. Rojas, How to Make Zuse's Z3 a Universal Computer.