diff --git a/doc/resources.md b/doc/resources.md
index f1282a2..09c2a1c 100644
--- a/doc/resources.md
+++ b/doc/resources.md
@@ -2,17 +2,17 @@
 
 ## Simple Neural Network
 - [3Blue1Brown](https://www.3blue1brown.com/topics/neural-networks)
-
-- [Neptune.ai](https://neptune.ai/blog/backpropagation-algorithm-in-neural-networks-guide)
-
+- [Medium](https://medium.com/@14prakash/back-propagation-is-very-simple-who-made-it-complicated-97b794c97e5c)
 - [Simeon Kostadinov: Understanding Backpropagation](https://towardsdatascience.com/understanding-backpropagation-algorithm-7bb3aa2f95fd)
-
 - [Tobias Hill: Gradient Descent](https://towardsdatascience.com/part-2-gradient-descent-and-backpropagation-bf90932c066a)
 
 ## Convolutional Neural Network
 
+- [The Independent Code](https://www.youtube.com/watch?v=Lakz2MoHy6o)
+
 ## Jeux de données
 - [MNIST](http://yann.lecun.com/exdb/mnist/)
+- [ImageNet](https://www.image-net.org/index.php)
 
 ## CUDA
 - [Introduction à CUDA](https://developer.nvidia.com/blog/even-easier-introduction-cuda/) (Documentation Nvidia)
diff --git a/src/cnn/cnn.c b/src/cnn/cnn.c
index 03daa07..7581005 100644
--- a/src/cnn/cnn.c
+++ b/src/cnn/cnn.c
@@ -6,6 +6,7 @@
 #include "include/initialisation.h"
 #include "include/function.h"
 #include "include/creation.h"
+#include "include/update.h"
 #include "include/make.h"
 
 #include "../include/colors.h"
@@ -130,85 +131,6 @@ void copy_input_to_input_z(float*** output, float*** output_a, int output_depth,
     }
 }
 
-void update_weights(Network* network) {
-    int n = network->size;
-    int input_depth, input_width, output_depth, output_width;
-    Kernel* k_i;
-    Kernel* k_i_1;
-    for (int i=0; i<(n-1); i++) {
-        k_i = network->kernel[i];
-        k_i_1 = network->kernel[i+1];
-        input_depth = network->depth[i];
-        input_width = network->width[i];
-        output_depth = network->depth[i+1];
-        output_width = network->width[i+1];
-
-        if (k_i->cnn) { // Convolution
-            Kernel_cnn* cnn = k_i_1->cnn;
-            int k_size = cnn->k_size;
-            for (int a=0; a<input_depth; a++) {
-                for (int b=0; b<output_depth; b++) {
-                    for (int c=0; c<k_size; c++) {
-                        for (int d=0; d<k_size; d++) {
-                            cnn->w[a][b][c][d] += cnn->d_w[a][b][c][d];
-                        }
-                    }
-                }
-            }
-        } else if (k_i->nn) { // Full connection
-            if (input_depth==1) { // Vecteur -> Vecteur
-                Kernel_nn* nn = k_i_1->nn;
-                for (int a=0; a<input_width; a++) {
-                    for (int b=0; b<output_width; b++) {
-                        nn->weights[a][b] += nn->d_weights[a][b];
-                    }
-                }
-            } else { // Matrice -> vecteur
-                Kernel_nn* nn = k_i_1->nn;
-                int input_size = input_width*input_width*input_depth;
-                for (int a=0; a<input_size; a++) {
-                    for (int b=0; b<output_width; b++) {
-                        nn->weights[a][b] += nn->d_weights[a][b];
-                    }
-                }
-            }
-        } else { // Pooling
-            (void)0; // Ne rien faire pour la couche pooling
-        }
-    }
-}
-
-void update_bias(Network* network) {
-    int n = network->size;
-    int output_width, output_depth;
-    Kernel* k_i;
-    Kernel* k_i_1;
-    for (int i=0; i<(n-1); i++) {
-        k_i = network->kernel[i];
-        k_i_1 = network->kernel[i+1];
-        output_width = network->width[i+1];
-        output_depth = network->depth[i+1];
-
-        if (k_i->cnn) { // Convolution
-            Kernel_cnn* cnn = k_i_1->cnn;
-            for (int a=0; a<output_depth; a++) {
-                for (int b=0; b<output_width; b++) {
-                    for (int c=0; c<output_width; c++) {
-                        cnn->bias[a][b][c] += cnn->d_bias[a][b][c];
-                    }
-                }
-            }
-        } else if (k_i->nn) { // Full connection
-            Kernel_nn* nn = k_i_1->nn;
-            for (int a=0; a<output_width; a++) {
-                nn->bias[a] += nn->d_bias[a];
-            }
-        } else { // Pooling
-            (void)0; // Ne rien faire pour la couche pooling
-        }
-    }
-}
-
 float compute_mean_squared_error(float* output, float* wanted_output, int len) {
     if (len==0) {
         printf("Erreur MSE: la longueur de la sortie est de 0 -> division par 0 impossible\n");
diff --git a/src/cnn/creation.c b/src/cnn/creation.c
index 7a004ef..582a224 100644
--- a/src/cnn/creation.c
+++ b/src/cnn/creation.c
@@ -29,7 +29,9 @@ Network* create_network(int max_size, int learning_rate, int dropout, int initia
     network->kernel[0]->nn = NULL; 
     network->kernel[0]->cnn = NULL; 
     create_a_cube_input_layer(network, 0, input_depth, input_dim); 
-    create_a_cube_input_z_layer(network, 0, input_depth, input_dim); 
+    // create_a_cube_input_z_layer(network, 0, input_depth, input_dim); 
+    // This shouldn't be used (if I'm not mistaken) so to save space, we can do:
+    ntework->input_z[0] = NULL; // As we don't backpropagate the input
     return network;
 }
 
@@ -104,7 +106,7 @@ void add_2d_average_pooling(Network* network, int dim_output) {
     network->kernel[k_pos]->nn = NULL;
     network->kernel[k_pos]->activation = 100*kernel_size; // Ne contient pas de fonction d'activation
     create_a_cube_input_layer(network, n, network->depth[n-1], network->width[n-1]/2);
-    create_a_cube_input_z_layer(network, n, network->depth[n-1], network->width[n-1]/2);
+    create_a_cube_input_z_layer(network, n, network->depth[n-1], network->width[n-1]/2); // Will it be used ?
     network->size++;
 }
 
@@ -130,33 +132,26 @@ void add_convolution(Network* network, int depth_output, int dim_output, int act
     cnn->columns = depth_output;
     cnn->w = (float****)malloc(sizeof(float***)*depth_input);
     cnn->d_w = (float****)malloc(sizeof(float***)*depth_input);
-    cnn->last_d_w = (float****)malloc(sizeof(float***)*depth_input);
     for (int i=0; i < depth_input; i++) {
         cnn->w[i] = (float***)malloc(sizeof(float**)*depth_output);
         cnn->d_w[i] = (float***)malloc(sizeof(float**)*depth_output);
-        cnn->last_d_w[i] = (float***)malloc(sizeof(float**)*depth_output);
         for (int j=0; j < depth_output; j++) {
             cnn->w[i][j] = (float**)malloc(sizeof(float*)*kernel_size);
             cnn->d_w[i][j] = (float**)malloc(sizeof(float*)*kernel_size);
-            cnn->last_d_w[i][j] = (float**)malloc(sizeof(float*)*kernel_size);
             for (int k=0; k < kernel_size; k++) {
                 cnn->w[i][j][k] = (float*)malloc(sizeof(float)*kernel_size);
                 cnn->d_w[i][j][k] = (float*)malloc(sizeof(float)*kernel_size);
-                cnn->last_d_w[i][j][k] = (float*)malloc(sizeof(float)*kernel_size);
             }
         }
     }
     cnn->bias = (float***)malloc(sizeof(float**)*depth_output);
     cnn->d_bias = (float***)malloc(sizeof(float**)*depth_output);
-    cnn->last_d_bias = (float***)malloc(sizeof(float**)*depth_output);
     for (int i=0; i < depth_output; i++) {
         cnn->bias[i] = (float**)malloc(sizeof(float*)*bias_size);
         cnn->d_bias[i] = (float**)malloc(sizeof(float*)*bias_size);
-        cnn->last_d_bias[i] = (float**)malloc(sizeof(float*)*bias_size);
         for (int j=0; j < bias_size; j++) {
             cnn->bias[i][j] = (float*)malloc(sizeof(float)*bias_size);
             cnn->d_bias[i][j] = (float*)malloc(sizeof(float)*bias_size);
-            cnn->last_d_bias[i][j] = (float*)malloc(sizeof(float)*bias_size);
         }
     }
     create_a_cube_input_layer(network, n, depth_output, bias_size);
@@ -188,14 +183,11 @@ void add_dense(Network* network, int output_units, int activation) {
     nn->output_units = output_units;
     nn->bias = (float*)malloc(sizeof(float)*output_units);
     nn->d_bias = (float*)malloc(sizeof(float)*output_units);
-    nn->last_d_bias = (float*)malloc(sizeof(float)*output_units);
     nn->weights = (float**)malloc(sizeof(float*)*input_units);
     nn->d_weights = (float**)malloc(sizeof(float*)*input_units);
-    nn->last_d_weights = (float**)malloc(sizeof(float*)*input_units);
     for (int i=0; i < input_units; i++) {
         nn->weights[i] = (float*)malloc(sizeof(float)*output_units);
         nn->d_weights[i] = (float*)malloc(sizeof(float)*output_units);
-        nn->last_d_weights[i] = (float*)malloc(sizeof(float)*output_units);
     }
     create_a_line_input_layer(network, n, output_units);
     create_a_line_input_z_layer(network, n, output_units);
@@ -227,14 +219,11 @@ void add_dense_linearisation(Network* network, int output_units, int activation)
     
     nn->bias = (float*)malloc(sizeof(float)*output_units);
     nn->d_bias = (float*)malloc(sizeof(float)*output_units);
-    nn->last_d_bias = (float*)malloc(sizeof(float)*output_units);
     nn->weights = (float**)malloc(sizeof(float*)*input_units);
     nn->d_weights = (float**)malloc(sizeof(float*)*input_units);
-    nn->last_d_weights = (float**)malloc(sizeof(float*)*input_units);
     for (int i=0; i < input_units; i++) {
         nn->weights[i] = (float*)malloc(sizeof(float)*output_units);
         nn->d_weights[i] = (float*)malloc(sizeof(float)*output_units);
-        nn->last_d_weights[i] = (float*)malloc(sizeof(float)*output_units);
     }
     /* Not currently used
     initialisation_1d_matrix(network->initialisation, nn->bias, output_units, output_units+input_units);
diff --git a/src/cnn/free.c b/src/cnn/free.c
index c4092b6..445572e 100644
--- a/src/cnn/free.c
+++ b/src/cnn/free.c
@@ -40,34 +40,27 @@ void free_convolution(Network* network, int pos) {
         for (int j=0; j < bias_size; j++) {
             free(k_pos->bias[i][j]);
             free(k_pos->d_bias[i][j]);
-            free(k_pos->last_d_bias[i][j]);
         }
         free(k_pos->bias[i]);
         free(k_pos->d_bias[i]);
-        free(k_pos->last_d_bias[i]);
     }
     free(k_pos->bias);
     free(k_pos->d_bias);
-    free(k_pos->last_d_bias);
 
     for (int i=0; i < r; i++) {
         for (int j=0; j < c; j++) {
             for (int k=0; k < k_size; k++) {
                 free(k_pos->w[i][j][k]);
                 free(k_pos->d_w[i][j][k]);
-                free(k_pos->last_d_w[i][j][k]);
             }
             free(k_pos->w[i][j]);
             free(k_pos->d_w[i][j]);
-            free(k_pos->last_d_w[i][j]);
         }
         free(k_pos->w[i]);
         free(k_pos->d_w[i]);
-        free(k_pos->last_d_w[i]);
     }
     free(k_pos->w);
     free(k_pos->d_w);
-    free(k_pos->last_d_w);
 
     free(k_pos);
 }
@@ -79,15 +72,12 @@ void free_dense(Network* network, int pos) {
     for (int i=0; i < dim; i++) {
         free(k_pos->weights[i]);
         free(k_pos->d_weights[i]);
-        free(k_pos->last_d_weights[i]);
     }
     free(k_pos->weights);
     free(k_pos->d_weights);
-    free(k_pos->last_d_weights);
 
     free(k_pos->bias);
     free(k_pos->d_bias);
-    free(k_pos->last_d_bias);
 
     free(k_pos);
 }
@@ -99,15 +89,12 @@ void free_dense_linearisation(Network* network, int pos) {
     for (int i=0; i < dim; i++) {
         free(k_pos->weights[i]);
         free(k_pos->d_weights[i]);
-        free(k_pos->last_d_weights[i]);
     }
     free(k_pos->weights);
     free(k_pos->d_weights);
-    free(k_pos->last_d_weights);
 
     free(k_pos->bias);
     free(k_pos->d_bias);
-    free(k_pos->last_d_bias);
 
     free(k_pos);
 }
diff --git a/src/cnn/include/function.h b/src/cnn/include/function.h
index a3fdcf8..344edb2 100644
--- a/src/cnn/include/function.h
+++ b/src/cnn/include/function.h
@@ -48,6 +48,9 @@ void choose_apply_function_matrix(int activation, float*** input, int depth, int
 */
 void choose_apply_function_vector(int activation, float*** input, int dim);
 
+/*
+* Renvoie la fonction d'activation correspondant à son identifiant (activation)
+*/
 ptr get_function_activation(int activation);
 
 #endif
\ No newline at end of file
diff --git a/src/cnn/include/struct.h b/src/cnn/include/struct.h
index d630e3a..d8c6224 100644
--- a/src/cnn/include/struct.h
+++ b/src/cnn/include/struct.h
@@ -7,10 +7,8 @@ typedef struct Kernel_cnn {
     int columns; // Depth of the output
     float*** bias; // bias[columns][dim_output][dim_output]
     float*** d_bias; // d_bias[columns][dim_output][dim_output]
-    float*** last_d_bias; // last_d_bias[columns][dim_output][dim_output]
     float**** w; // w[rows][columns][k_size][k_size]
     float**** d_w; // d_w[rows][columns][k_size][k_size]
-    float**** last_d_w; // last_d_w[rows][columns][k_size][k_size]
 } Kernel_cnn;
 
 typedef struct Kernel_nn {
@@ -18,10 +16,8 @@ typedef struct Kernel_nn {
     int output_units; // Nombre d'éléments en sortie
     float* bias; // bias[output_units]
     float* d_bias; // d_bias[output_units]
-    float* last_d_bias; // last_d_bias[output_units]
     float** weights; // weight[input_units][output_units]
     float** d_weights; // d_weights[input_units][output_units]
-    float** last_d_weights; // last_d_weights[input_units][output_units]
 } Kernel_nn;
 
 typedef struct Kernel {
diff --git a/src/cnn/include/update.h b/src/cnn/include/update.h
new file mode 100644
index 0000000..345060f
--- /dev/null
+++ b/src/cnn/include/update.h
@@ -0,0 +1,26 @@
+#ifndef DEF_UPDATE_H
+#define DEF_UPDATE_H
+
+/*
+* Met à jours les poids à partir de données obtenus après plusieurs backpropagations
+* Puis met à 0 tous les d_weights
+*/
+void update_weights(Network* network);
+
+/*
+* Met à jours les biais à partir de données obtenus après plusieurs backpropagations
+* Puis met à 0 tous les d_bias
+*/
+void update_bias(Network* network);
+
+/*
+* Met à 0 toutes les données de backpropagation de poids
+*/
+void reset_d_weights(Network* network);
+
+/*
+* Met à 0 toutes les données de backpropagation de biais
+*/
+void reset_d_bias(Network* network);
+
+#endif
\ No newline at end of file
diff --git a/src/cnn/update.c b/src/cnn/update.c
new file mode 100644
index 0000000..aab9c8f
--- /dev/null
+++ b/src/cnn/update.c
@@ -0,0 +1,165 @@
+
+#include "update.h"
+
+void update_weights(Network* network) {
+    int n = network->size;
+    int input_depth, input_width, output_depth, output_width;
+    Kernel* k_i;
+    Kernel* k_i_1;
+    for (int i=0; i<(n-1); i++) {
+        k_i = network->kernel[i];
+        k_i_1 = network->kernel[i+1];
+        input_depth = network->depth[i];
+        input_width = network->width[i];
+        output_depth = network->depth[i+1];
+        output_width = network->width[i+1];
+
+        if (k_i->cnn) { // Convolution
+            Kernel_cnn* cnn = k_i_1->cnn;
+            int k_size = cnn->k_size;
+            for (int a=0; a<input_depth; a++) {
+                for (int b=0; b<output_depth; b++) {
+                    for (int c=0; c<k_size; c++) {
+                        for (int d=0; d<k_size; d++) {
+                            cnn->w[a][b][c][d] += cnn->d_w[a][b][c][d];
+                            cnn->d_w[a][b][c][d] = 0;
+                        }
+                    }
+                }
+            }
+        } else if (k_i->nn) { // Full connection
+            if (input_depth==1) { // Vecteur -> Vecteur
+                Kernel_nn* nn = k_i_1->nn;
+                for (int a=0; a<input_width; a++) {
+                    for (int b=0; b<output_width; b++) {
+                        nn->weights[a][b] += nn->d_weights[a][b];
+                        nn->d_weights[a][b] = 0;
+                    }
+                }
+            } else { // Matrice -> vecteur
+                Kernel_nn* nn = k_i_1->nn;
+                int input_size = input_width*input_width*input_depth;
+                for (int a=0; a<input_size; a++) {
+                    for (int b=0; b<output_width; b++) {
+                        nn->weights[a][b] += nn->d_weights[a][b];
+                        nn->d_weights[a][b] = 0;
+                    }
+                }
+            }
+        } else { // Pooling
+            (void)0; // Ne rien faire pour la couche pooling
+        }
+    }
+}
+
+void update_bias(Network* network) {
+    int n = network->size;
+    int output_width, output_depth;
+    Kernel* k_i;
+    Kernel* k_i_1;
+    for (int i=0; i<(n-1); i++) {
+        k_i = network->kernel[i];
+        k_i_1 = network->kernel[i+1];
+        output_width = network->width[i+1];
+        output_depth = network->depth[i+1];
+
+        if (k_i->cnn) { // Convolution
+            Kernel_cnn* cnn = k_i_1->cnn;
+            for (int a=0; a<output_depth; a++) {
+                for (int b=0; b<output_width; b++) {
+                    for (int c=0; c<output_width; c++) {
+                        cnn->bias[a][b][c] += cnn->d_bias[a][b][c];
+                        cnn->d_bias[a][b][c] = 0;
+                    }
+                }
+            }
+        } else if (k_i->nn) { // Full connection
+            Kernel_nn* nn = k_i_1->nn;
+            for (int a=0; a<output_width; a++) {
+                nn->bias[a] += nn->d_bias[a];
+                nn->d_bias[a] = 0;
+            }
+        } else { // Pooling
+            (void)0; // Ne rien faire pour la couche pooling
+        }
+    }
+}
+
+void reset_d_weights(Network* network) {
+    int n = network->size;
+    int input_depth, input_width, output_depth, output_width;
+    Kernel* k_i;
+    Kernel* k_i_1;
+    for (int i=0; i<(n-1); i++) {
+        k_i = network->kernel[i];
+        k_i_1 = network->kernel[i+1];
+        input_depth = network->depth[i];
+        input_width = network->width[i];
+        output_depth = network->depth[i+1];
+        output_width = network->width[i+1];
+
+        if (k_i->cnn) { // Convolution
+            Kernel_cnn* cnn = k_i_1->cnn;
+            int k_size = cnn->k_size;
+            for (int a=0; a<input_depth; a++) {
+                for (int b=0; b<output_depth; b++) {
+                    for (int c=0; c<k_size; c++) {
+                        for (int d=0; d<k_size; d++) {
+                            cnn->d_w[a][b][c][d] = 0;
+                        }
+                    }
+                }
+            }
+        } else if (k_i->nn) { // Full connection
+            if (input_depth==1) { // Vecteur -> Vecteur
+                Kernel_nn* nn = k_i_1->nn;
+                for (int a=0; a<input_width; a++) {
+                    for (int b=0; b<output_width; b++) {
+                        nn->d_weights[a][b] = 0;
+                    }
+                }
+            } else { // Matrice -> vecteur
+                Kernel_nn* nn = k_i_1->nn;
+                int input_size = input_width*input_width*input_depth;
+                for (int a=0; a<input_size; a++) {
+                    for (int b=0; b<output_width; b++) {
+                        nn->d_weights[a][b] = 0;
+                    }
+                }
+            }
+        } else { // Pooling
+            (void)0; // Ne rien faire pour la couche pooling
+        }
+    }
+}
+
+void reset_d_bias(Network* network) {
+    int n = network->size;
+    int output_width, output_depth;
+    Kernel* k_i;
+    Kernel* k_i_1;
+    for (int i=0; i<(n-1); i++) {
+        k_i = network->kernel[i];
+        k_i_1 = network->kernel[i+1];
+        output_width = network->width[i+1];
+        output_depth = network->depth[i+1];
+
+        if (k_i->cnn) { // Convolution
+            Kernel_cnn* cnn = k_i_1->cnn;
+            for (int a=0; a<output_depth; a++) {
+                for (int b=0; b<output_width; b++) {
+                    for (int c=0; c<output_width; c++) {
+                        cnn->d_bias[a][b][c] = 0;
+                    }
+                }
+            }
+        } else if (k_i->nn) { // Full connection
+            Kernel_nn* nn = k_i_1->nn;
+            for (int a=0; a<output_width; a++) {
+                nn->d_bias[a] = 0;
+            }
+        } else { // Pooling
+            (void)0; // Ne rien faire pour la couche pooling
+        }
+    }
+}
\ No newline at end of file
diff --git a/test/cnn_convolution.cu b/test/cnn_convolution.cu
index f092431..28c863d 100644
--- a/test/cnn_convolution.cu
+++ b/test/cnn_convolution.cu
@@ -104,16 +104,13 @@ void run_convolution_test(int input_dim, int output_dim, int rows, int columns)
     // bias[kernel->columns][dim_output][dim_output]
     kernel->bias = create_matrix(kernel->columns, output_dim, output_dim, 15.0f);
     kernel->d_bias = create_matrix(kernel->columns, output_dim, output_dim, 1.5f);
-    kernel->last_d_bias = create_matrix(kernel->columns, output_dim, output_dim, 0.1f);
 
     // w[rows][columns][k_size][k_size]
     kernel->w = (float****)malloc(sizeof(float***)*kernel->rows);
     kernel->d_w = (float****)malloc(sizeof(float***)*kernel->rows);
-    kernel->last_d_w = (float****)malloc(sizeof(float***)*kernel->rows);
     for (int i=0; i < kernel->rows; i++) {
         kernel->w[i] = create_matrix(kernel->columns, kernel->k_size, kernel->k_size, 15.0f);
         kernel->d_w[i] = create_matrix(kernel->columns, kernel->k_size, kernel->k_size, 1.5f);
-        kernel->last_d_w[i] = create_matrix(kernel->columns, kernel->k_size, kernel->k_size, 0.1f);
     }
 
     float*** input = create_matrix(kernel->rows, input_dim, input_dim, 5.0f);
@@ -151,16 +148,13 @@ void run_convolution_test(int input_dim, int output_dim, int rows, int columns)
 
     free_matrix(kernel->bias, kernel->columns, output_dim);
     free_matrix(kernel->d_bias, kernel->columns, output_dim);
-    free_matrix(kernel->last_d_bias, kernel->columns, output_dim);
 
     for (int i=0; i < kernel->rows; i++) {
         free_matrix(kernel->w[i], kernel->columns, kernel->k_size);
         free_matrix(kernel->d_w[i], kernel->columns, kernel->k_size);
-        free_matrix(kernel->last_d_w[i], kernel->columns, kernel->k_size);
     }
     free(kernel->w);
     free(kernel->d_w);
-    free(kernel->last_d_w);
 
     free_matrix(input, kernel->rows, input_dim);
     free_matrix(output_cpu, kernel->columns, output_dim);