C language

Comments
ASCII chart
Character sets and encodings
Translation phases
Punctuation
Identifier - Scope - Lifetime
Lookup and Name Spaces
Type - Arithmetic types
Objects and Alignment
The main function
As-if rule
Undefined behavior
Memory model and Data races

#if - #ifdef - #ifndef - #elif
#elifdef - #elifndef (C23)
#define - # - ##
#include - #pragma
#line - #error
#warning (C23) - #embed (C23)

if - switch
for
while - do-while
continue - break
goto - return

Value categories
Evaluation order and sequencing
Constants and literals
  Integer constants
  Floating constants
  Character constants
  true/false (C23)
  nullptr (C23)
  String literals
  Compound literals (C99)
Constant expressions
Implicit conversions
Operators
  Member access and indirection
  Logical - Comparison
  Arithmetic - Assignment
  Increment and Decrement
  Call, Comma, Ternary
  sizeof - alignof (C11)
  Cast operators
Operator precedence
Generic selection (C11)

Scalar
Array
Structure/Union

Pointers - Arrays
Enumerations
Storage duration and Linkage
const - volatile - restrict (C99)
struct - union - Bit-fields
alignas (C11) - typedef
static_assert (C11)
Atomic types (C11)
External and tentative definitions
Attributes (C23)

Function declaration
Function definition
inline (C99)
_Noreturn (C11) (deprecated in C23)
Variadic arguments

History of C
Conformance
Inline assembly
Signal handling
Analyzability (C11)