In my opinion, programming is about solving problems. We have different tools we use in different situations, like a hammer to hit the nail, and a screwdriver for tuning screws. We use each programming language depending on the problem, so the question really depends on the problems we encounter:
- For problems requiring performance, like the fastest way to sort a list, we prefer to use low-level languages which give tools to use all the potential of a computer;
- For complex problems, like managing a database, we prefer more abstract languages, to really focus on the constraints;
- For multi-platform programs, like an calculator application, we use more high level languages because we don't want to depend on the computer, etc.
The first programming language we learn is not a matter of pride. At that time it could be a mistake for the problem we encounter. But it doesn't matter because we learn from our tries and we continue to program.
My first program was a quiz made with Excel worksheet. I think it was really cool and I want to extend functionalities, so I use VB. Then I read a book about C89 and I tested it and I love it, then C++ to use SDL library to make a game. Nowadays, I have a range of tools to use, even though I started with a program that is not even a language.
To answer the question, I don't want to give a list of programming languages to discover, but if we want to write goods programs, we need to understand how it works. It is like a car, when we learn to drive a car, we learn how it is working, so we know why it is impossible to shift gears when we move back for example.
I think it is really important to know how a CPU works if we use low-level languages, how a garbage collector works if we use Java, how page caching works if we write web pages, etc.
This knowledge is acquired depending on our way to learn. Some people prefer to read a book, some people read source code, some experiment and try to break the program.
There is no ultimate way to learn programming, and each developer history is really interesting, because it reflects our passion on solving problems.