C

Scope

Provides lexical scope to eliminate global variables
Functions exist in global namespace
Functions may not be declared within other functions

Typing

Variable are statically typed
Type rules are weakly enforced
Implicit conversions are possible

Running C Programs

Compile to executable: gcc source.c --output executable
Run the executable: ./executable
tcc can run C compile and run in one step: tcc -run source.c

int a = 1;
float b = 2.0;

printf("%f\n", a + b); // Prints 3.0

char * a = 1;
int b = 2;

printf("%d\n", a + b); // Prints 3