This kind of title appears once in a while in feeds and in search results about languages (I do search for languages trends).
I want to make my own list. I am not going to suggest a language because they can give you a job, high salary, or because it’s what all the buzz is about. These factors mean nothing.
I am not going to explain why you should learn something about all those languages: you will get it once you study them!
Some languages allow nested functions (or procedures, or subroutines, or whatever you prefer to call them), others don't.
I think those can be useful and I wonder why they aren't embraced by all living programming languages.
In a previous post I've imagined that future C++ could dynamically dispatch a call to a proper function/method according to the derived types of its arguments — that is, dynamic overloading, whereas notoriously in C++ overloading is a compile time feature.
Now the question is: what about other languages?
Twitter has the limit of 140 characters per tweet, and this limit is even reduced when you add media contents like images. Now that Twitter is “consumed” through the web, there wouldn't be serious reasons not to rise that limit.