For practical implementation I followed his tutorials:
Contents on Neural Networks (Each of the view is a PDF)
vertopal.com_01_NeuralNetwork.pdf
vertopal.com_01_NeuralNetwork_Larger.pdf
vertopal.com_02_neural_network_classification.pdf
vertopal.com_03_convolutional.pdf
vertopal.com_03_convolutional2.pdf