Programming & scripting languages
Literature
On the free Ebook foundation website, you will find an overview of a bunch of programming e-books (PDF/ HTML) free of charge for almost any language in the areas of
Regular programming (e.g. C, C++, C#, Java, Go, MATLAB, PHP, Rust, Scala, ...)
Scripting (e.g. JavaScript, make, Perl, Python, R, Ruby, Unix/ Windows Shells, SQL, ...)
Document rendering (e.g. HTML, CSS, LaTeX, ...)
Multiprocessing/ parallel computing APIs (e.g. OpenMP, ...)
Programming related tools (e.g. Git, Subversion, Mercurial, Jenkins, ...)
Programming languages