diff --git a/neuronal_network.h b/neuronal_network.h
index c0d14c8..c2b3c8c 100644
--- a/neuronal_network.h
+++ b/neuronal_network.h
@@ -1,7 +1,37 @@
 #pragma once
 
 typedef struct {
-    Matrix* input;
-    Matrix* output;
+    int input_size;
+    //Matrix* input; as local variable given to function
 
-} Neuronal_Network;
\ No newline at end of file
+    // hidden layers
+    int hidden_size;
+    Matrix* weights_1;
+    Matrix* bias_1;
+    Matrix* weights_2;
+    Matrix* bias_2;
+    Matrix* weights_3;
+    Matrix* bias_3;
+
+    int output_size = 10;
+    Matrix* weights_output;
+    //Matrix* bias_output; // do we need it?
+    //Matrix* output; as local variable given to function
+
+    double learning_rate;
+
+} Neural_Network;
+
+Neural_Network* new_network(int input_size, int hidden_size, int output_size, double learning_rate);
+void print_network(Neural_Network* network);
+void free_network(Neural_Network* network);
+
+void save_network(Neural_Network* network, char* file);
+Neural_Network* load_network(char* file);
+
+double predict_images(Neural_Network* network, Image** images, int amount);
+Matrix* predict_image(Neural_Network* network, Image*);
+Matrix* predict(Neural_Network* network, Matrix* image_data);
+
+void train_network(Neural_Network* network, Matrix* input, Matrix* output);
+void batch_train_network(Neural_Network* network, Image** images, int size);
\ No newline at end of file