What the word neural buys

The title of this track uses a borrowed word, neural. It comes from the cells of the brain. This lesson checks what it means here.

The rule

A neuron here is one unit. It adds inputs times weights, then compares the sum to a threshold. A network is many units joined. This track built one unit.

A neuron is a loose name for one of these units. The name is borrowed from brain cells. It has inputs, weights, a sum, a threshold, a verdict. A neural network is a loose name for many such units. That name is borrowed too. The units are joined, so one unit's verdict becomes another unit's input. A computer network is computers joined so they can pass messages. A neural network is also made of joined parts. The parts are units.

Books draw a network in layers. The input layer takes in the data. The hidden layers sit between input and output. The output layer gives the answer. Each layer is made of units like ours. Our unit takes inputs and works out one result.

The word does not show that our unit works like a brain. A real brain cell does much more than add and compare. The word alone does not show a product is good. And it does not mean we built a network. This track never joined two units.

Below are two units, A and B. A is the finished unit of this track. Move the gauge and the days. Then join B to A. A's verdict becomes B's input. Make B say call.

Try the lab to finish this lesson.