C Programming
Pointers, memory and the machine: the language that operating systems and embedded devices are written in.
Beginner
Start here. No background needed beyond school maths.
Beej's Guide to C Programming
A friendly, complete guide to C that covers pointers, memory and strings plainly, with many small examples. Free to read online.
Sign up to see the source
C Reference (cppreference)
The standard online reference for the C language and its standard library, with a page for every header and function.
Sign up to see the source
CS50x: Introduction to Computer Science
••••'s free first course in computer science. The first weeks teach programming in C, so you meet memory, pointers and the compiler early, with problem sets you can check yourself.
Sign up to see the source
Learn C
Short interactive lessons in the browser: variables, arrays, loops, pointers and structs, each with a small exercise you run on the spot.
Sign up to see the source