I started by writing C programs for coursework in college. Then I worked part-time for several companies using assembly for embedded controllers, Visual Basic and Delphi for Windows desktop apps.

After coming to US to work on PhD I used MATLAB plus C/Fortran for control design tools several years. And for coursework I switched to JAVA as required by most classes.

After graduation I worked at MathWorks, where I use C++ for primary and MATLAB for secondary.

In my spare time I found python and loved it ever since for its syntax.

After several years I used C++ primary, MATLAB and OCaml both secondary. OCaml is very nice because it encourages thinking in terms of functions, which is very close to the way people think when they are doing formal research.

While studying OCaml I found scala. I liked it very much for its rich type system and language features. I used in my work as a prototyping language.

Having said a lot about languages, I still believe what my advisor told me: language does not matter, it is what the person writes that matters.