It is hard to vote for a single programming language here. But yes, we can categorize them into two parts. First of all, if we talk about the best frontend programming languages, then I would say JavaScript and HTML are my damn favourite client-side programming languages because they are not easy to learn but also work very effectively. Probably, this article
https://blog.back4app.com/front-end-programming-languages/ is also going to tell you a lot about the best frontend programming languages.
On the contrary, if we talk about the backend languages, then I will vote for Python. Yes, it is one of the most popular backend development languages because of its open-source wide library and simple syntax. Social networking sites like Pinterest and Instagram are also using Python for their backend programming.
There are no shortcuts in Life.