diff --git a/src/multiplication.c b/src/multiplication.c
new file mode 100644
index 0000000..1832133
--- /dev/null
+++ b/src/multiplication.c
@@ -0,0 +1,264 @@
+#include "multiplication.h"
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
+
+double multi( double ein1, double ein2) {
+    return (ein1 * ein2);
+}
+
+double square(double x) {
+    return x * x;
+}
+
+int multiply_three_integers(int a, int b, int c) {
+    return a * b * c;
+}
+
+int multiply_left_shift(int a, int b) {
+    return a << b;
+}
+int multiply_right_shift(int a, int b) {
+    return a >> b;
+}
+int multiply_by_ten(int a) {
+    return a * 10;
+}
+
+float multiply_by_percentage(float num, float percentage) {
+    return num * (percentage / 100);
+}
+
+int multiply_by_random(int num) {
+    int random_factor = random_factor % 10 + 1; 
+    return num * random_factor;
+}
+
+int multiply_string(const char* str, int factor) {
+    int len = strlen(str);
+    int result = 0;
+    for (int i = 0; i < len; i++) {
+        result += str[i] * factor;
+    }
+    return result;
+}
+
+int multiply_by_sum(int num1, int num2) {
+    return num1 * (num2 + 1);
+}
+
+int multiply_using_two_complements(int num1, int num2) {
+    int result = 0;
+    while (num1 != 0) {
+        if (num1 & 1) {
+            result += num2;
+        }
+        num1 >>= 1;
+        num2 <<= 1;
+    }
+    return result;
+}
+
+int multiply_by_even(int num, int factor) {
+    return (num >> 1) << (factor + 1);
+}
+
+int multiply_using_lookup_table(int num1, int num2) {
+    int lookup_table[10][10] = {
+        {0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+        {0, 1, 2, 3, 4, 5, 6, 7, 8, 9},
+        {0, 2, 4, 6, 8, 10, 12, 14, 16, 18},
+        {0, 3, 6, 9, 12, 15, 18, 21, 24, 27},
+        {0, 4, 8, 12, 16, 20, 24, 28, 32, 36},
+        {0, 5, 10, 15, 20, 25, 30, 35, 40, 45},
+        {0, 6, 12, 18, 24, 30, 36, 42, 48, 54},
+        {0, 7, 14, 21, 28, 35, 42, 49, 56, 63},
+        {0, 8, 16, 24, 32, 40, 48, 56, 64, 72},
+        {0, 9, 18, 27, 36, 45, 54, 63, 72, 81}
+    };
+    return lookup_table[num1][num2];
+}
+
+int multiply_using_logical_operations(int num1, int num2) {
+    int result = 0;
+    while (num2) {
+        if (num2 & 1) {
+            result ^= num1;
+        }
+        num1 <<= 1;
+        num2 >>= 1;
+    }
+    return result;
+}
+
+int multiply_using_modulo(int num1, int num2, int modulo) {
+    return (num1 % modulo) * (num2 % modulo) % modulo;
+}
+
+int multiply_by_prime(int num, int prime) {
+    return num * (prime - 1) + num;
+}
+
+int multiply_using_increment(int num1, int num2) {
+    int result = 0;
+    for (int i = 0; i < num2; ++i) {
+        result += num1;
+    }
+    return result;
+}
+
+int multiply_by_prime_and_its_square(int num, int prime) {
+    return num * (prime + square (prime));
+}
+
+int multiply_by_odd(int num, int factor) {
+    int result = 0;
+    for (int i = 0; i < factor; ++i) {
+        result += num;
+    }
+    return result;
+}
+
+int multiply_using_binary_enumeration(int num1, int num2) {
+    int result = 0;
+    while (num1 && num2) {
+        if (num2 & 1) {
+            result += num1;
+        }
+        num1 <<= 1;
+        num2 >>= 1;
+    }
+    return result;
+}
+
+int multiply_using_differences(int num1, int num2) {
+    int difference = (num1 > num2) ? num1 - num2 : num2 - num1;
+    int sum = (num1 > num2) ? num1 + num2 : num2 + num1;
+    return (sum - difference) * difference / 4;
+}
+
+int multiply_recursive_optimized(int num1, int num2) {
+    if (num2 == 0) {
+        return 0;
+    }
+    int result = multiply_recursive_optimized(num1, num2 >> 1);
+    result <<= 1;
+    if (num2 & 1) {
+        result += num1;
+    }
+    return result;
+}
+
+int multiply_octal_numbers(int num1, int num2) {
+    int result = 0;
+    while (num2 != 0) {
+        if (num2 & 1) {
+            result += num1;
+        }
+        num1 <<= 3; // Décalage octal
+        num2 >>= 1;
+    }
+   
+    return result;
+}
+
+int multiply_hex_numbers(int num1, int num2) {
+    int result = 0;
+    while (num2 != 0) {
+        if (num2 & 1) {
+            result += num1;
+        }
+        num1 <<= 4; 
+        num2 >>= 1;
+    }
+    return result;
+}
+
+int multiply_exponentiation(int base, int exponent) {
+    int result = 1;
+    while (exponent > 0) {
+        if (exponent & 1) {
+            result *= base;
+        }
+        base *= base;
+        exponent >>= 1;
+    }
+    return result;
+}
+
+int multiply_by_euler_prime(int num) {
+    return (num << 1) + (num << 2) - num;
+} 
+
+int fibonacci_multiply(int num, int fib) {
+    return num * fib;
+}
+
+int repeated_division_multiply(int num1, int num2) {
+    int result = 0;
+    while (num1 > 0) {
+        if (num1 % 2 == 1) {
+            result += num2;
+        }
+        num1 >>= 1;
+        num2 <<= 1;
+    }
+    return result;
+} 
+
+int bernoulli_multiply(int num, int bernoulli) {
+    return num * bernoulli;
+}
+
+float power_multiply(float base, int exponent) {
+    float result = 1.0;
+    for (int i = 0; i < exponent; i++) {
+        result *= base;
+    }
+    return result;
+}
+
+int bitwise_multiply(int num1, int num2) {
+    int result = 0;
+    while (num1) {
+        if (num1 & 1) {
+            result += num2;
+        }
+        num1 >>= 1;
+        num2 <<= 1;
+    }
+    return result;
+}
+
+int karatsuba_multiply(int num1, int num2) {
+    // Base case: If numbers are less than 10, return their product directly
+    if (num1 < 10 || num2 < 10) {
+        return num1 * num2;
+    }
+
+    int m = (int)fmax(log10(num1), log10(num2)) + 1; // Maximum length of numbers
+    int m2 = m / 2; // Divide maximum length by two
+
+    // Divide numbers into parts
+    int a = num1 / pow(10, m2);
+    int b = num1 % (int)pow(10, m2);
+    int c = num2 / pow(10, m2);
+    int d = num2 % (int)pow(10, m2);
+
+    // Calculate intermediate products
+    int ac = karatsuba_multiply(a, c);
+    int bd = karatsuba_multiply(b, d);
+    int ad_bc = karatsuba_multiply(a + b, c + d) - ac - bd;
+
+    // Calculate the final result
+    return ac * (int)pow(10, 2 * m2) + ad_bc * (int)pow(10, m2) + bd;
+}
+
+
+
+
+
+
+    
+
diff --git a/src/multiplication.h b/src/multiplication.h
new file mode 100644
index 0000000..8653b4a
--- /dev/null
+++ b/src/multiplication.h
@@ -0,0 +1,41 @@
+#ifndef MULTIPLICATION_H
+#define MULTIPLICATION_H
+extern double multi(double ein1, double ein2);
+double square(double x);
+int multiply_three_integers(int a, int b, int c);
+int multiply_left_shift(int a, int b);
+int multiply_right_shift(int a, int b);
+int multiply_by_ten(int a);
+float multiply_by_percentage(float num, float percentage);
+int multiply_by_random(int num);
+int multiply_string(const char* str, int factor);
+int multiply_by_sum(int num1, int num2);
+int multiply_using_two_complements(int num1, int num2);
+int multiply_by_even(int num, int factor);
+int multiply_using_lookup_table(int num1, int num2);
+int multiply_using_logical_operations(int num1, int num2);
+int multiply_using_modulo(int num1, int num2, int modulo);
+int multiply_by_prime(int num, int prime);
+int multiply_using_increment(int num1, int num2);
+int multiply_by_prime_and_its_square(int num, int prime);
+int multiply_by_odd(int num, int factor);
+int multiply_using_binary_enumeration(int num1, int num2);
+int multiply_using_differences(int num1, int num2);
+int multiply_recursive_optimized(int num1, int num2);
+int multiply_octal_numbers(int num1, int num2);
+int multiply_hex_numbers(int num1, int num2);
+int multiply_exponentiation(int base, int exponent);
+int multiply_by_euler_prime(int num);
+int fibonacci_multiply(int num, int fib);
+int repeated_division_multiply(int num1, int num2);
+int bernoulli_multiply(int num, int bernoulli);
+float power_multiply(float base, int exponent);
+int bitwise_multiply(int num1, int num2);
+int karatsuba_multiply(int num1, int num2);
+
+
+
+
+
+#endif // MULTIPLICATION_H
+
diff --git a/test/test_multiplication.c b/test/test_multiplication.c
new file mode 100644
index 0000000..1f564ac
--- /dev/null
+++ b/test/test_multiplication.c
@@ -0,0 +1,20 @@
+#ifdef TEST
+
+#include "unity.h"
+
+#include "multiplication.h"
+
+void setUp(void)
+{
+}
+
+void tearDown(void)
+{
+}
+
+void test_multiplication_NeedToImplement(void)
+{
+    TEST_IGNORE_MESSAGE("Need to Implement multiplication");
+}
+
+#endif // TEST