Artificial neural networks and deep learning

Neural networks are among the most commonly used models in machine learning and were inspired by the structure of the human brain. The basic building blocks of these networks are nodes, or neurons, which are based on the biological neuron cell, as depicted in the following diagram:

Biological neuron model
Source: https://pixabay.com/vectors/neuron-nerve-cell-axon-dendrite-296581/

The neuron cell's dendrites, which are surrounding the cell body on the left-hand side of the preceding diagram, are used as inputs from multiple similar cells, while the long axon, coming out of the cell body, serves as output and can be connected to multiple other cells.

This structure is mimicked by the artificial model called the perceptron, illustrated as follows:

Artificial neuron model – the perceptron

The perceptron calculates the output...