Why does one use a particular programming language for a particular thing...

Question

why does one use swift for iOS and not python or c++...why doesnt on use swift and c# for web development instead of javascript.....

Answer 1

In some cases there is a defined standard for development on a platform. That is the case of Apple, if you want to develop something for their line of operating systems the first choice should be their languages (although there are always some alternatives). And something similar happens with the web, although you have a lot of languages that can replace JS, most of them do not have the support that JS offers among browsers, so either they are not viable or you need to compile them to JS (although there are very interesting technologies to change this).

In other cases, the choice of a tool may not be as defined, and it goes directly through the choice of the developer and its management of each tool.