programming languages

What language do use use or recommend learning? Why do you use it, or what is it most useful for? What is the most efficient language to use when working with chess.com api or development?

I like Java a lot, as it is (relatively) easy to use and learn. Python and Javascript are very useful but they take more work to understand when you get into the more advanced features. (They aren't terrible for a first programming language, but I somewhat dislike them personally.) Bash is extremely useful on Mac/Linux/etc. for working with files and such. For work with REST APIs (e.g. chess.com's API) just about anything will do, so pick your language based on appropriateness of use (that is, don't use Java to download one web page, and don't use Python for a 10GB code base).

I store most of my data so I use VBA / Excel

Python (vers.3x) for me. Very useful general purpose object-oriented language with a lot of support online. So many people use it that there always seems to be someone who can answer a question, or has already solved some coding problem.

I use it for fetching (mostly) match endpoint data & for recalculating match scores, taking into account closed accounts (cheats). The Requests module for web downloads is a breeze to use, once you get the hang of it.

I created application to consume API in C#, its a desktop application.

I use C++, it's very powerful and good for an application where efficiency is important, but takes more work than some of the others.

I use Python as well. Extremely useful not only for chess.com API but also for automatisation of everyday routine.

In fact plenty of programming languages can operate with JSON and web requests, so a choice of the language is a question of the platform. If you want to create an android application - go to learn Java, Apple application - Swift.

I am also a Python fan. It is simple to use, and has tons of documentation and online support.

For chess.com data and api, in general, you're going to find Python probably the easiest to use and best supported. Secondary to this, JavaScript, but for the fact you've got two primary branches: Web development, and Node.js (server-side scripting). If you're going to consume and present data, then you should probably start with JavaScript (aside from likely also needing to know or learn HTML/CSS). If you're just shuttling data around, I recommend Python.

If you find any of Python's numeric libraries too slow for crunching numbers or data, then you should consider a lower-level language like Java or C++ or C#. IMO: You can't usually do data or number crunching in JavaScript (or, rather, you shouldn't).

In truth, it really depends on what you want to do, how fast you want to do it, and how much time you have to invest in learning before wanting to see results. Shortest and fastest path is likely Python, followed by JavaScript (based on relative support and overall usage across developer channels).