C

The foundational language for modern computing, operating systems, and embedded systems.

When to Use

• Operating Systems / Drivers
• Embedded Systems
• High-performance computing
• Legacy codebases

Quick Start

#include <stdio.h>

int main() {
    printf("Hello, World!\n");
    return 0;
}

Core Concepts

Pointers

Variables that store memory addresses.

int x = 10;
int *p = &x; // p holds address of x
printf("%d", *p); // Dereference p to get 10

Memory Management

Manual allocation and deallocation.

int *arr = (int*)malloc(10 * sizeof(int));
// use arr...
free(arr);

Structs

User-defined data types.

Best Practices

Do:

• Always initialized variables
• Check return values of malloc
• Guard against buffer overflows (use snprintf over sprintf)
• Use tools like Valgrind to check for leaks

Don’t:

• Return pointers to local variables (stack memory)
• Use gets() (unsafe)

References

• C Reference