diff --git a/src/typeDefinitions.h b/src/constants.h
similarity index 55%
rename from src/typeDefinitions.h
rename to src/constants.h
index 1e956970..d097d9b1 100644
--- a/src/typeDefinitions.h
+++ b/src/constants.h
@@ -22,11 +22,34 @@
 * THE SOFTWARE.                                                                 *
 ********************************************************************************/
 
-#ifndef TYPEDEFINITIONS_H
-#define	TYPEDEFINITIONS_H
+#ifndef CONSTANTS_H
+#define	CONSTANTS_H
+
+// Libraries
+#include <limits>
 
 // Type definitions
 typedef unsigned int uint;
 
+// Mathematical constants
+const double EPSILON = 0.00001;                                             // Epsilon value to avoid numerical errors
+const double ONE_MINUS_EPSILON = 0.99999;                                   // 1 - espilon
+const double INFINITY_CONST = std::numeric_limits<double>::infinity();      // Infinity constant
+const double PI = 3.14159265;                                               // Pi constant
+
+// Contact constants
+const double FRICTION_COEFFICIENT = 0.4;    // Friction coefficient
+const double PENETRATION_FACTOR = 0.2;      // Penetration factor (between 0 and 1) which specify the importance of the
+                                            // penetration depth in order to calculate the correct impulse for the contact
+
+// Constraint solver constants
+const uint MAX_LCP_ITERATIONS = 10;         // Maximum number of iterations when solving a LCP problem
+const double AV_COUNTER_LIMIT = 500;        // Maximum number value of the avBodiesCounter or avConstraintsCounter
+const double AV_PERCENT_TO_FREE = 0.5;      // We will free the memory if the current nb of bodies (or constraints) is
+                                            // less than AV_PERCENT_TO_FREE * bodiesCapacity (or constraintsCapacity). This
+                                            // is used to avoid to keep to much memory for a long time if the system doesn't
+                                            // need that memory. This value is between 0.0 and 1.0
+
+
 #endif
 
diff --git a/src/constraint/Contact.h b/src/constraint/Contact.h
index 569e9a55..4d0d7de4 100644
--- a/src/constraint/Contact.h
+++ b/src/constraint/Contact.h
@@ -26,9 +26,9 @@
 #define CONTACT_H
 
 // Libraries
-#include "../typeDefinitions.h"
 #include "Constraint.h"
 #include "../body/RigidBody.h"
+#include "../constants.h"
 #include "../mathematics/mathematics.h"
 #include <GL/freeglut.h>        // TODO : Remove this in the final version
 #include <GL/gl.h>              // TODO : Remove this in the final version
@@ -36,11 +36,6 @@
 // ReactPhysics3D namespace
 namespace reactphysics3d {
 
-// Constants
-const double FRICTION_COEFFICIENT = 0.3;    // Friction coefficient
-const double PENETRATION_FACTOR = 0.0;      // Penetration factor (between 0 and 1) which specify the importance of the
-                                            // penetration depth in order to calculate the correct impulse for the contact
-
 /*  -------------------------------------------------------------------
     Class Contact :
         This class represents a collision contact between two bodies in
diff --git a/src/engine/ConstraintSolver.h b/src/engine/ConstraintSolver.h
index e7d5760f..b4489516 100644
--- a/src/engine/ConstraintSolver.h
+++ b/src/engine/ConstraintSolver.h
@@ -26,7 +26,7 @@
 #define CONSTRAINTSOLVER_H
 
 // Libraries
-#include "../typeDefinitions.h"
+#include "../constants.h"
 #include "../constraint/Constraint.h"
 #include "../mathematics/lcp/LCPSolver.h"
 #include "ContactCache.h"
@@ -37,14 +37,6 @@
 // ReactPhysics3D namespace
 namespace reactphysics3d {
 
-// Constants
-const uint MAX_LCP_ITERATIONS = 10;     // Maximum number of iterations when solving a LCP problem
-const double AV_COUNTER_LIMIT = 500;    // Maximum number value of the avBodiesCounter or avConstraintsCounter
-const double AV_PERCENT_TO_FREE = 0.5;  // We will free the memory if the current nb of bodies (or constraints) is
-                                        // less than AV_PERCENT_TO_FREE * bodiesCapacity (or constraintsCapacity). This
-                                        // is used to avoid to keep to much memory for a long time if the system doesn't
-                                        // need that memory. This value is between 0.0 and 1.0
-
  /*  -------------------------------------------------------------------
     Class ConstrainSolver :
         This class represents the constraint solver. The goal is to
diff --git a/src/mathematics/Matrix.cpp b/src/mathematics/Matrix.cpp
index 2eb4a49c..4aa15b46 100644
--- a/src/mathematics/Matrix.cpp
+++ b/src/mathematics/Matrix.cpp
@@ -99,7 +99,6 @@ Matrix::Matrix(const Matrix3x3& matrix)
     }
 }
 
-
 // Conversion from Vector to Matrix
 Matrix::Matrix(const Vector& vector) {
         // Create the two dimensional dynamic array
@@ -112,59 +111,6 @@ Matrix::Matrix(const Vector& vector) {
         }
 }
 
-// TODO : Delete this
-Matrix::Matrix(const Matrix6x6& matrix) : nbRow(6), nbColumn(6) {
-    // Create the two dimensional dynamic array
-    array = new double*[nbRow];
-
-    assert(array != 0);     // Array pointer musn't be null
-
-    for(int i=0; i<nbRow; ++i) {
-        array[i] = new double[nbColumn];
-    }
-
-    // Copy the matrix
-    for (int i=0; i<nbRow; ++i) {
-        for(int j=0; j<nbColumn; ++j) {
-            setValue(i,j, matrix.getValue(i,j));
-        }
-    }
-}
-
-// TODO : Delete this
-Matrix::Matrix(const Matrix1x6& matrix) : nbRow(1), nbColumn(6) {
-    // Create the two dimensional dynamic array
-    array = new double*[nbRow];
-
-    assert(array != 0);     // Array pointer musn't be null
-
-    for(int i=0; i<nbRow; ++i) {
-        array[i] = new double[nbColumn];
-    }
-
-    // Copy the matrix
-        for(int j=0; j<nbColumn; ++j) {
-            setValue(0,j, matrix.getValue(j));
-        }
-}
-
-// TODO : Delete this
-Matrix::Matrix(const Vector6D& vector) :nbRow(6), nbColumn(1) {
-    // Create the two dimensional dynamic array
-    array = new double*[nbRow];
-
-    assert(array != 0);     // Array pointer musn't be null
-
-    for(int i=0; i<nbRow; ++i) {
-        array[i] = new double[nbColumn];
-    }
-
-    // Copy the matrix
-        for(int j=0; j<nbRow; ++j) {
-            setValue(j,0, vector.getValue(j));
-        }
-}
-
 // Destructor of the class Matrix
 Matrix::~Matrix() {
     // Destruction of the dynamic array
diff --git a/src/mathematics/Matrix.h b/src/mathematics/Matrix.h
index f0735dde..4a2e221a 100644
--- a/src/mathematics/Matrix.h
+++ b/src/mathematics/Matrix.h
@@ -57,9 +57,6 @@ class Matrix {
         Matrix(const Matrix& matrix);                                                                                   // Copy constructor of the class Matrix
         Matrix(const Matrix3x3& matrix);                                                                                // Conversion from Matrix3x3
         Matrix(const Vector& vector);                                                                                   // Conversion from Vector to Matrix
-        Matrix(const Matrix6x6& matrix);
-        Matrix(const Matrix1x6& matrix);
-        Matrix(const Vector6D& vector);
         virtual ~Matrix();                                                                                              // Destructor of the class Matrix
         double getValue(int i, int j) const throw(std::invalid_argument);                                               // Return a value in the matrix
         void setValue(int i, int j, double value) throw(std::invalid_argument);                                         // Set a value in the matrix
diff --git a/src/mathematics/Vector.h b/src/mathematics/Vector.h
index b56eb806..7eb53aec 100644
--- a/src/mathematics/Vector.h
+++ b/src/mathematics/Vector.h
@@ -27,7 +27,7 @@
 
 // Libraries
 #include "Vector3D.h"
-#include "../typeDefinitions.h"
+#include "../constants.h"
 #include "mathematics_functions.h"
 #include "exceptions.h"
 #include <cmath>
diff --git a/src/mathematics/constants.h b/src/mathematics/constants.h
index 34a10429..a7776c90 100644
--- a/src/mathematics/constants.h
+++ b/src/mathematics/constants.h
@@ -26,12 +26,6 @@
 #define CONSTANTS_H
 
 // Libraries
-#include <limits>
 
-// Constants
-const double EPSILON = 0.00001;
-const double ONE_MINUS_EPSILON = 0.99999;
-const double INFINITY_CONST = std::numeric_limits<double>::infinity();
-const double PI = 3.14159265;               // Pi constant
 
 #endif
diff --git a/src/mathematics/lcp/LCPSolver.h b/src/mathematics/lcp/LCPSolver.h
index 90daaeaf..651e276f 100644
--- a/src/mathematics/lcp/LCPSolver.h
+++ b/src/mathematics/lcp/LCPSolver.h
@@ -26,7 +26,7 @@
 #include "../Vector.h"
 #include "../Matrix.h"
 #include "../../body/Body.h"
-#include "../../typeDefinitions.h"
+#include "../../constants.h"
 
 // ReactPhysics3D namespace
 namespace reactphysics3d {
diff --git a/src/mathematics/mathematics.h b/src/mathematics/mathematics.h
index b00ae03e..85631fd1 100644
--- a/src/mathematics/mathematics.h
+++ b/src/mathematics/mathematics.h
@@ -31,7 +31,7 @@
 #include "Quaternion.h"
 #include "Vector.h"
 #include "Vector3D.h"
-#include "constants.h"
+#include "../constants.h"
 #include "exceptions.h"
 #include "mathematics_functions.h"
 #include <vector>
diff --git a/src/mathematics/mathematics_functions.h b/src/mathematics/mathematics_functions.h
index 2a45a0fd..7b8d77f5 100644
--- a/src/mathematics/mathematics_functions.h
+++ b/src/mathematics/mathematics_functions.h
@@ -26,7 +26,7 @@
 #define MATHEMATICS_FUNCTIONS_H
 
 // Libraries
-#include "constants.h"
+#include "../constants.h"
 
 // ReactPhysics3D namespace
 namespace reactphysics3d {