A to Z of C

by K. Joseph Wesley, R. Rajesh Jeba Anbiah

DOS C

Modern GPU

by Sean Baxter

Build Your Own Lisp

by Daniel Holden

Let's Build a Compiler

by Jack Crenshaw

Think OS

by Allen B. Downey

C OS

Tutorials for modern OpenGL

by opengl-tutorial.org

ØMQ - The Guide

by Pieter Hintjens