Any sufficiently analyzed magic is indistinguishable from science
~Girl Genius Online
Computers are all around us. Obvious examples are Smartphones, Game Consoles, and other "Smart" Appliances like Televisions. There are also computers hiding in surprising places you may not expect, such as Wireless Routers or Printers. When such a diverse set of devices can all be described with a single word, one begins to wonder: What's a Computer?
A Computer is a device that can perform useful work by executing millions of tiny steps in an ordered collection called a Program. Critical components include the Motherboard, Memory, Central Processing Unit (CPU), and Inputs/Outputs (I/O). In time we'll discuss each of these in detail, but we'll start with a basic overview.
A Motherboard is a large Printed Circuit Board (PCB) which connects every other component together. It's the first component to receive power when the device is powered on. Connected components are able to communicate with each other over electrical pathways called "Buses".
When we talk about a computer having "Memory", what we're really talking about is a working area to process, transform, hold onto, and re-arrange Data, similar in principle to how you might use a piece of scratch paper. When we put something into this workspace, we need to be able to retrieve it quickly no matter where it is located within. Just as the Post Office communicates where mail should go, regions of memory are referenced by their "Address". This kind of arbitrary location-based retrieval is the eponymous "Random Access" in Random Access Memory (RAM).
The CPU executes atomic units of work called "Instructions". These kinds of operations are so small, you'd hardly believe they could ever be useful. We're talking about complexity at the level of "put this number over there". But don't let their seeming simplicity fool you; every program that has ever been written or ever will be written is comprised of these kinds of tiny building blocks.
Last but not least, we have I/O. These are all the various physical connection points that allow us to connect to external devices or components such as Input Methods like a Keyboard or Mouse, or Output Devices like a Display or Speakers. Some external devices act as both input and output, such as an External Storage Medium like a Hard Drive. For any data to enter or exit the world inside the computer, it must first pass through the I/O.
In concert, a Computer is far greater than the sum of its parts. When we put all these pieces together we can accomplish truly amazing things. We can calculate additional digits of pi, achieving precision many orders of magnitude above and beyond what one could ever apply in practice. We can simulate aspects of the physical world such as how differently-shaped objects affect and are affected by oncoming headwinds. This power increases exponentially when connecting multiple computers together, allowing us to communicate with people and cultures on every continent, even with astronauts aboard the International Space Station.
Computers make all this and so much more possible. They are among the most powerful tools we have ever devised, but this promethean bargain also places them among our most dangerous. Easily as they can connect us, they can divide us. Quickly as they can spread truth and peace, they can spread fear and strife. With great power, there must also come great responsibility.
Despite their place at the center of all our lives, how these machines really work is oft-regarded as a Realm of the Arcane, inscrutable to all but a select few, far beyond the grasp of "mere mortals". This could not be further from the truth.
Information wants to be free, so if you are someone for whom knowledge of this domain has felt inaccessible, it is by no means because you are simply of an "inferior sort". Rather it is because this information has been systematically obscured by jargon and withheld by gatekeepers. In this series I hope to cut through the noise and de-mystify the subject matter for anyone and everyone, regardless of technical acumen or personal background.
Journey with me through the forces by which our modern world has been built and broken alike. Welcome to the Human's Guide to Computers.