00 What are these things we call computers?

Computers are all around us these days.

We think we know what they are, but do we really? Should we?

To a certain extent, they have become invisible, hiding in our portable phones and our entertainment centers, in our fridges, washers, microwave ovens, ...

They are at the center of arguments about patents and copyrights and very large amounts of money that corporations are claiming other corporations owe them.

We keep our records and organize our lives using them. They control the payment of our wages and fees, and they control the movement of money when we buy things, even when we buy things with cash. They control our bank accounts and phone systems.

Some people want to use them to control our elections.

Do we dare not know what they are?

I don't think so.

You can research them on Wikipedia, and learn a lot, but there is much that you probably won't learn from even the best encyclopedias, without having someone point it out to you.

I have spent most of my life studying them and working with and on them. I want to share my (somewhat biased) point of view, because I think my point of view can help untangle a lot of the more vicious knots that our current society is tangled up in.

In order to use computers well and wisely, we must understand them to a certain extent. We should understand what we mean by the word, and what we intend by the concept. We must understand their capabilities, and we must understand their inherent limitations.

The approach I will take is to start with a brief overview of the history of computers and their uses.

In the process, I will discuss the definitions of the word "computer", historically, and in current use.

I hope that the definitions I present will motivate an interest in what can and can't be done with computers. At any rate, that's what I will tackle next.

But, in order to talk about what can and cannot be done with them, I will have to provide an introduction to elements of the mathematical theories of computation. I'm not really qualified to speak formally about the theories, but I think I can explain the concepts and give an overview of the implications.

Thus: