Basically, there are two main types of programming languages. Interpreted and compiled. An interpreted language has to use an "engine" to work. Compiled language has an engine of its own.
Interpreted languages like PHP, Python, Java, C# are normally slower when executed. You can read and copy the source code of an interpreted language. PHP is the most used "web language" of them all. Used by millions, but also used by thousands of hackers.
Compiled languages like C, C++, Rust, Go are way faster when executed. The source code of an compiled language is harder to "copy" as humans can not read them. This makes the life harder for the hacker.
Therefore, I chose a compiled language. The fastest languages today are C, C++ and Rust, AFAIK. Go is not that fast, but it is much easier to learn.
One thing that I found interesting is that it has a built-in web server. You do not need Apache or Nginx. Neither do you need an "app engine".