That all depends on the application, I guess ;-)<p>Usually I end-up using Python for smaller things that aren&#x27;t mission-critical or need maximum performance, C++ for almost everything else, and Objective-C for OS X&#x2F;iOS stuff. Maybe Java for things where both performance, safety and ease-of-development&#x2F;maintenance matter (the latter would be mostly for other people who would have to work on the same projection who are less skilled in C++, as I&#x27;m not at all a fan of the language myself, but I recognize it has some properties that make it a suitable choice for many kinds of applications ;-). I don&#x27;t have enough experience with any other programming languages that can be deployed easily across Linux and OS X, so I can&#x27;t comment on those. Rust seems to have some good ideas so I may want to learn more about it in the future.<p>If I wanted to write something for Windows platforms I&#x27;d most likely gravitate towards C#, from what I know about the language it appears to have all the good things of Java without its downsides.