C

1. GNU C Language Manual

   Language reference covering types, expressions, statements, functions, and pointers.

2. Data Types and Pointers

   Integer, floating-point, array, struct, union, enum types, and pointers.

3. Expressions and Operators

   Operators, precedence, and conversions.

4. Statements

   Control flow statements and loops.

5. Functions

   Function definitions, calls, and recursion.

6. Variables and Storage

   Variable declarations, scope, storage classes, and type qualifiers.

7. GNU C Library: Memory and Strings

   Memory allocation and the C standard library.

8. Input/Output Streams

   Streams, files, and low-level I/O.

9. Processes and Signals

   Process creation and signal handling.

10. GCC Compiler

    GCC options, extensions, and warnings.

11. ISO C Standard (WG14)

    The ISO/IEC C standard committee.

Each section links to the official page. Titles and summaries by Extra Credit; the docs belong to their authors.