How computers work

How do computers work? It's a complex subject, but I'm going to give it a shot.

By computers, I mean information appliances, including, but not limited to, personal computers, larger computers, tablets, and smartphones.

I'll start with an attempt at diagramming the important parts of computers:

The graphic is a link to a larger version of the chart.

The diagram above, complex as it is, leaves out a lot. Perhaps the most important entity that it leaves out is perhaps the most important kind of software -- personal data. Documents, presentations, graphics, videos, music, eBooks, and other items that we, the users, have created, or that we have obtained from other sources.

Hardware and software

Computers require hardware, physical equipment. There are many kinds of hardware, including cases, monitors or viewing screens, touchscreens, physical memory, cables, mice, trackpads, keyboards, processing units, modems, routers, printers, computer projectors, wi-fi receiver/transmitters, speakers, and a lot more. These are all physically tangible, although often, they are hidden inside the case.

Software is information of some sort, that is stored, for intervals ranging for the life of the processing unit or hard disk, to for a very short time. There are several kinds of software, including operating systems, application software (or apps), hardware drivers, utilities, and data. One thing that I need to say about information -- it's stored, and passed on, as some sort of binary data -- a string of 1's and 0's, represented as pulses of electric charge, as tiny areas on a  memory chip, either magnetized or not, or in some other way. If you could dissect an information appliance, you aren't going to find anything that looks like a picture. Pictures are assembled, by software, from these pulses or magnetized areas. I'm  going to discuss these types of software below.

A cynical way to look at the difference between hardware and software is that, if all goes well, eventually, you can get software to work, but that, eventually, hardware will fail and stop working.

Software should sometimes be updated. The manufacturer may find an error in the software, as originally sold or distributed, and corrects that, or adds capability to an application, or finds a vulnerability to a virus or other malware in an operating system. Microsoft updates Windows several times a year. When an update becomes available, you should usually update the software. Some updating is automatic, provided the information appliance has an Internet connection.

Operating systems

Operating systems include the instructions that make an information appliance into something more than an expensive doorstop or paperweight -- when it is turned on, the operating system, after a delay (called booting up) tells the information appliance "You are now a computer, or smartphone, or whatever it is." They also do other things, such as help the user communicate with the computer, for example by monitoring the keyboard and sending the information input in that way to the operating system, a utility, or an application. They read information from storage hardware.

Examples of operating systems include Windows (all versions) for Windows computers and tablets, Mountain Lion for iMacs, and Ice Cream Sandwich for Android tablets and smartphones. There should be an operating system already installed on any information appliance you purchase from an electronics store.

Operating systems also communicate with peripheral hardware, such as printers, and the viewing screen. They may communicate with a disk drive or other storage device.

Ideally, an operating system is so unobtrusive that a user doesn't even notice it, or may not even think that her information appliance has one.

Application software

Application software is designed to carry out a specific purpose, for example word processing, or allowing a user to play a particular game. Whereas all functioning information appliances have operating systems, the applications available may vary widely from one information appliance to another. You have probably seen this in comparing the appearance of two smartphones.

If I want to create a document of some sort, say a business letter, I do whatever the operating system requires, so that the computer retrieves a word processor application from storage. Then I type the letter. The operating system passes the information from each key, and from other ways of inputting, to the word processor. The word processor receives that information, and presents it as a string of letters, some capitalized, and punctuation, including spaces and line breaks, on the screen. Word is the most common word processor. There are many others.

Other applications, say Angry Birds, use few or no inputs from the keyboard, but are similar to word processors, in that the operating system starts them, and they take user input, in this case from finger movements and taps on a touchscreen, they display the result on the screen, and that they are for a specific purpose. You wouldn't use a word processor to calculate your taxes, and you can't use Angry Birds to play solitaire.

Browsers

A browser is a special type of application. Its purpose is to connect you with the Internet, although browsers can be used for other purposes. Many people use a browser to send and receive e-mail, and to access documents compatible with the web that are stored as data on their information appliance. Examples include Internet Explorer, Firefox, Chrome, Opera, Safari, Dolphin, and the stock Android browser. (That is, the one that comes installed on devices with an Android operating system, such as Ice Cream Sandwich.)

Browsers, like all applications, are under the control of the operating system, and use the operating system to communicate with the user. Browsers usually look up information on the Internet, under the control of the user, and present the contents of a web page to the user. Entering a URL, such as "http://en.wikipedia.org/wiki/Web_browser" or the simpler "en.wikipedia.org," or typing a search term or phrase, tells the browser where to go on the Internet. Clicking on a link also tells the browser where to go.

Browsers usually have extensions. A common one is Adobe Reader, which lets the browser present .PDF files to the user. Another one is the Flash player, which allows the browser to present some types of multimedia. Other extensions may attempt to block access to dangerous web sites, or keep track of passwords for you. There are many other extensions.

Some applications can connect to the Internet without using a browser. This is often true of e-mail applications and utilities, and is true of some apps.

Hardware drivers

Hardware drivers work with the operating system to communicate with various kinds of peripheral hardware, such as printers, cameras, a mouse, and others. Printers, say, are not all alike. Even printers made by the same manufacturer are not all alike. The operating system sends information from an application, such as a word processor, to a printer driver, which, as it were, translates that information to the language used by the particular printer, which, in turn, prints out a document.

Most hardware comes with a driver installed, but there are times when the operating system will tell you, as it were, "I don't know how to communicate with this type of device." For example, if a new type of camera comes out a couple of years after your computer, most likely there won't be a driver for this camera installed on the computer. You may have purchased a CD with the camera driver along with the camera, or it may be necessary for the operating system to search the Internet for a driver, or you may have to go to the manufacturer's web site and locate a driver and download it and install it, in order to use that camera with our computer.

Utilities work with the operating system to do various things. Perhaps the most common type of utility is anti-virus software. Another handy type of utility is a program that tells you which software you need to update, and helps to update it for you.

Data

Data is a general name for information that you create, or that someone else makes available to you. There are many types, including text documents, messages, books, web pages, pictures, presentations, spreadsheets, game scores, music, videos, and others.

User-created data, such as term papers, financial information, and photos, may be extremely important. Because this is true, it should be backed up frequently. That is, it should be copied onto an external storage device, or to Internet storage sites. I use a flash drive, and copy all the data files created or saved, say, during the last three days, onto it, then copy from the flash drive to a second computer. Twice a month, I copy at least that months files to an external hard drive.

Thanks for directing your browser and the operating system to access this web page.

I'm an information junkie. Are you?

I confess. I'm an information junkie. If I see part of a sporting event on TV, I want to know who won it, even if I've never seen the team, or individual, before. I listen to National Public Radio news programs a lot, and I often stay in the car after arriving at my destination, because I want to hear the rest of the story. I read a lot, on-line and in classical media. When the Watergate Hearings were on TV, I watched a lot of them. I didn't need to, but I wanted to. My wife and I have four information appliances in our home. I don't think we are ever actively using all four at once, but we often use two at a time, and occasionally three. Maybe you are like that. Maybe not. In this day of Twitter, texting while driving, libraries, magazine sales at the checkout counter, GPS devices, walking with earbuds in your ears, hundreds of TV channels, and lots and lots of on-line sites, including some apparently important ones that I've never heard of, a lot of people out there must be like that.

I guess I should stop and say that "information" has a technical meaning, or several such. I used an information appliance to look that linked source up, by the way.

Why am I like this? Why are you? I'm not sure. Part of it is that we need to know things for various reasons, such as to rear our children, do our job, study the Bible, converse with other people. Some of it must be that wanting to know things must be part of the image of God in us. Unfortunately, some of our information searching is sinful, however. Seeking out pornography, stealing someone's identity, finding out about things that we covet, when we don't need them, being a fan of the wrong sort of celebrity, seeking out stuff to gossip about, in various ways, are bending information hunger into wrong directions.

Am I ever going to see all of the sports events on TV, no matter how many channels I have at my disposal? Am I ever going to know all of the news being pumped out? Am I ever going to read all the books I've thought about reading? No. Neither are you.

Is that bad? Not necessarily. Most of the stories I can look at, in all kinds of media, have little value now. Almost none of them will have much importance ten years from now. Very, very few of them will have any importance in 2112.

There's a moral in that last paragraph. I need to pay attention to it. What's that moral? Ultimately, there's only one story that's of eternal importance. That's the story of Christ. He created, He sustains, He lived for us, died for us, was resurrected for us, and, by His death and resurrection, paid the penalty for our sins. He is now waiting for us. That story makes the Southeast Conference, National Public Radio, NBC, the local newspaper, all the magazines available at the supermarket, all the sites on the Internet, all the books in the library, all the tweets in cyberspace seem so insignificant that it's hardly worth paying attention to them, in comparison.

Thanks for reading. I hope that wasn't too much information!

On being an information addict

I recently mused on the question of whether or not St. Paul was a multi-tasker. (The post contains a link to a report on research indicating that multitasking is bad for your thinking.) I'd like to muse, in this post, on the broader question of why anyone might want to be one.

One answer is that some of us have more to do than we really can do. So we feed the baby while we catch up on the news, or take phone calls while stirring the recipe, or checking the e-mail. That's an unfortunately legitimate reason for multitasking, provided, of course, that we haven't taken on more than we should have, doing things we really don't need to.

Another reason is that we have tools which enable us to multitask. I am using an information appliance to write this. You are using an information appliance to read this -- unless someone else has used an information appliance to print this out for you. We have this equipment, so we think we should use it. I didn't have many opportunities to multitask when I was a boy. Although I am not yet eighty years old, I did grow up in a home with no telephone, until I had been in college for a while. If I wanted to communicate with my parents from college, I wrote a post card. I also made sure that I had made future arrangements carefully, since I usually couldn't change them. We certainly had no computer, no television, and no newspaper. (We did have radios.) I couldn't multitask then like I can now, although my father set an example of how to multitask without a phone, TV, or computer, by listening to the radio in the barn, while he was milking cows, with a pulp magazine opened on one leg, pumping out the milk while reading and listening. (He read a lot of fantastic literature.) The radio was the only information appliance he had, and, except for being able to change stations, or the volume, it was a one-way appliance. We received. We didn't broadcast to anybody else.

Not only do some people almost have to multitask, because they have too much to do, and some because they have an information appliance which helps them multitask, but, I submit, there is a third reason -- all of us are information addicts, to a greater or less degree.

Babies show this by paying attention to all sorts of things. Some people show it by watching soap operas. Some show it by paying close attention to the minutiae of some sport, or some favorite team. Some show it by paying close attention to some politician, or to a performer, or even a person prominent because of their religion, or to our own little clique of friends or co-workers. I remember paying far more attention than I should have to the Watergate affair. If I'm not careful, I'll pay too much attention to the trials and tribulations of my current state governor. Some of us are news junkies, with CNN or some other such venue on the TV all the time, or sent regularly to another information appliance. Some of us have way too many Facebook or Twitter contacts, far more than we can reasonably keep up with. (One of my Facebook Friends once suggested -- on Facebook, of course -- that there should be a "Who Cares" button for new entries.) Some of us want to know and hear the latest music, or see the latest fashions, or the news from the markets, the latest recipes, or (oh-oh!) the latest gossip, pure and simple -- not that a lot of the other activities in this paragraph aren't also gossip.

Why do we do this? One reason is that we are suckers for anything new. I suspect that one reason that Eve listened to the serpent was that the serpent said something she hadn't heard or thought of before. Acts 17:21 gives us a description of the Athenians: "Now all the Athenians and the foreigners who lived there would spend their time in nothing except telling or hearing something new." (ESV) (Not to challenge the truth of the Bible, but surely there were slaves, and probably other working people in Athens who didn't have time to spend in such a pursuit.) But we like to do this. We are, to some extent, information addicts.

New isn't necessarily bad. The Gospel, after all, is Good News. To people who have never heard it, getting this new information, by whatever means, is critical. Do I still have that hunger to know what God wants to say to me? I hope so, but I fear not.

New can be bad, and the worst thing it can do is to distract from the timeless. There are truths we must not forget, that are far more important than the latest doings in the organizations that are important to us. What are these truths? The Gospel, for one. God's love, and His goodness and holiness, for another. The beauty we see, hear, feel, and smell, in flowers, sunsets, dewdrops, good food, music, children, and laughter. A grandchild's laugh is more important than a sports score or whatever the President may have said. The existence of butterflies, waterfalls, rainbows, and bird songs is far more important than our current bank balance or how our mutual fund is doing. Does this mean that we should never pay attention to the news? Of course not. But it does mean that we need to cut back on our information addiction, and pay attention to what those we love, especially God, are telling us in common, ordinary, slow ways. Perhaps we should be more like J. R. R. Tolkien's hobbits, who, he wrote, ". . . like to have books filled with things they already know, set out fair and square with no contradictions." (Prologue, The Fellowship of the Ring -- Boston: Houghton Mifflin, 1954, p. 18.)

The Gospel, God's love, God's creation, and the possibility of meaningful relationships with others, are things that no information appliance will ever give you, or me. May I not forget what's really important, and eternal.

Thanks for using your information appliance.

Jan has written a good, and shorter, post which overlaps with this one.