Learning Computers And Science?

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yes it is. thanks

"C:\Users\Paul-denice\Desktop\kittens.html"
my webpage? works for me but not for others. thats why I said it comes up with some sort of error message. (i dont know the message itself) but perhaps you can tell me what it is?

See if you can express the algorithm independent of any computer language. This is sometimes called pseudo code and it is the counterpart of a gedanken experiment in physics. If you can comprehend an algorithm at the conceptual level then you can program it in just about any computer language. Do not let the language get between you and the idea.

ruveyn

(Note: it's important you don't skim this message, OP. If you read it at all, read it very carefully. Any sentence you don't completely understand, re-read. And read it a third time if you still have trouble. And if you still don't get it, even in context, then make a note to ask about it and then move on. If you want to do anything technical in life, you first need to learn how to read, which means not skimming parts just because they're boring.)

Skimming this thread, I can't decide if you're worth helping or not.

But looking at the above quote, I myself can't think of a book or website that I can point you to for you to read and figure out the answer on your own. It's simultaneously too simple and too complex.

So I'm going to answer this particular question very comprehensively, in the hopes that once you get over the bump you'll arrive in a territory where you can more easily learn on your own with limited external guidance.

The URL of this website is "http://www.wrongplanet.net/", usually with some more words after that, like in this particular case for me, "forums-posting-quote-p-5036269.html". Let's just look at the first part.

It starts with "http". You probably don't know what that means. You can wikipedia it, but you'll be clicking words all night and maybe still never get anywhere.

HTTP stands for "HyperText Transfer Protocol". It's a standard protocol that certain types of software use to communicate with each other. Most commonly, those are web browsers and web servers. (Another type of software that uses HTTP is a web crawler, like what Google uses to learn about your site so that it can return it in search results. As a programmer, I can also write software that uses HTTP for other weird purposes, like maybe submitting information directly to a webserver without using a web browser.)

Internet Explorer, Firefox, Chrome, Safari, mobile web browsers, those are all web browsers. You open them and surf the net. You know what they are.

Servers are something you've never played with before, most likely. They're a special kind of software. *Some* versions of Windows come with one called Internet Information Services, or IIS. Windows 7 Pro does, for instance, but Windows 7 Home might not. Even when they do, it's often a component you have to install from the Add Programs page. Linux usually offers a simple way to install Apache web server or one or two others. And there are several others.

What does a web server do, and how does it work? Not an easy question, but here's the cliff's notes.

I don't want the world to read my entire hard drive. You don't want the world to read yours. And historically, computers just didn't have a way to do that anyway; they're very dumb.

So we needed a way to tell the world "oh hey, you can read this particular part of my hard drive if you want!" And so we wrote a webserver. And then we ran it, and it just sits there running behind the scenes. It's not like Minesweeper where you have a window showing what it's doing; it just works behind the scenes and doesn't have to show anything. You see what it's doing by using a web browser.

Each server, though, comes with a tool that lets us give it instructions. So I open Internet Services Manager, which is the tool for managing IIS. In ISM, I say "okay, I want my website to be this directory here." And I point it to "C:\website\home" or whatever. And I say "and I want the default file to be "unicorns.html" or whatever. And I hit "OK" and close ISM.

Now I open my web browser, and I navigate to "http://localhost/". "localhost" is a special word in network protocols that points to the same machine it's used on. So if you run it, it points to your machine. if I run it, it points to mine.

When the web browser tries to load that webpage, it asks "localhost", my machine, if it's running a webserver. It is, so IIS responds with "sure, we're open for business, here's your default webpage!" and it sends back "unicorn.html" to the web browser, which renders it nice and pretty so I can look at it.

But if you tried to run "http://localhost/", you wouldn't see my webpage, because that's not my machine.

You could try my IP address if you knew it, like "http://1.2.3.4/", but you don't. (I don't either, offhand).

So there's this other thing called a "domain name". And that's where there are these other kinds of servers out there that your computer asks "he wants the webpage for domain 'wrongplanet.net', do you know where that is?" and the domain name server (literally, "DNS") sends back "yep! they're at 67.217.166.186". So your web browser says "thanks!" and loads "http://67.217.166.186/". If you try that, (and that is the actual wrongplanet.net IP address), you won't get wrongplanet.net's front page. Why? Because the webserver there actually hosts a bunch of sites, and unless it knows you're specifically asking for "wrongplanet.net", it won't know which of its sites to show you. So it shows you its default website instead.

Now, when you made your "kittens.html" file and saved it on your machine, that's great. And you can look at it through a web browser by telling the browser to look at your file address. And that works on your machine.

But MY machine can't see your files. It can only see files you share via a webserver. And since running your own webserver requires a static IP and some other things that most people don't have, you'd probably just use a third party hosting service, like any of the thousands of webhosting services that are on the net. They usually cost $5-$15 a month. Sometimes even lower; you can get great deals and service if you ask around. What they do is operate webservers for you, with static IP addresses (as opposed to dynamic IP addresses, which change frequently and thus aren't worth associating with a domain name or sharing with friends).

The service you select and pay for will tell you how to upload files to it. Maybe an FTP client, maybe just something on their websites, whatever. It's usually very simple and they tell you exactly how to do it.

Then you upload your "kittens.html" file to that hosting service, and specify that it's your default webpage.

Then you'd probably want a domain name to point at that website, like "keniichi.com". But that's probably taken, so maybe "dp_keniichi.com" or something. Or just use the IP address, that's okay too if you're just testing stuff and learning. In fact, that's better, because you aren't paying for a URL that you might end up not liking. So maybe your URL will be "http://123.123.1.2/" or something. Your hosting service will tell you your site's IP address, and typically you can use it directly rather than needing a domain name. Or it might be "http://www.fatcow.com/x/y/Keniichi/", if they've got a common URL for everything.

I think that explanation hits all the bases, though I'm sure I glossed over some important parts you need.

DO NOT ASK FOR A SIMPLER ANSWER. Complicated subjects require complicated explanations. Get used to reading complicated explanations and taking notes on things you don't understand. Look up any words you don't know, and post a list of questions about any specific parts you didn't get.

This page goes over a lot of what I said, and might help give you some more words to look up and learn about:

http://www.w3schools.com/hosting/host_intro.asp

This is what ISM looks like, not that you really need to know:

[img][800:721]http://comptechdoc.org/os/windows/win2kgraph/ism/ism.jpg[/img]

That screenshot shows a very complicated website with lots of directories doing weird stuff, but I couldn't find a simpler screenshot on bing. Notice the "postinfo.html" file on the right; that would be like your kittens.html. And you simply wouldn't have any of the other files or directories.

But again, you don't need a webserver at your stage anyway. Just use a hosting service if you use anything at all.

(In fact, most internet service providers offer free limited webhosting to their customers, so you may already have some hosting you can use. It'll have a long URL with lots of directories, but that's fine, nobody cares for testing purposes. Call your ISP and ask, the worst they can say is no.)

(This post only took me 20 minutes to write, if anyone's wondering whether I have no life.) (Though it's true I have no life.)

One more thing, OP. To answer your original question about how you learn this stuff, I would say, the hard way. As you've discovered, the hardest part is knowing what questions to ask. That's what they never teach kids in school. Once you have the question, you pretty much already have the answer. It's finding the questions that's difficult.

Wikipedia is a great resource. You can look up anything there, and whatever page you end up on, you'll have lots and lots of clickable links to similar topics. And you can read and explore pretty much indefinitely, going from webservers to http to networks to computers to hard drives to metallurgy to physics to falling to cats to whatever you want. It's a GREAT tool for finding similar topics that you don't already know about. So, "what other protocols are there besides HTTP?" On wikipedia, the first link in the HTTP definition is to http://en.wikipedia.org/wiki/Application_protocol, where you'll see all sorts of protocols, like Telnet, FTP, DNS (remember that?), email protocols, etc.

It really is a great resource; learn to use it. Even though the definitions can get very complicated, get used to reading them. The complexity is because they're trying to explain things as precisely as they can, in as short a definition as they can. There's no word on that site that you can't learn if you look it up. And the more you do that, the easier it will be to read or talk about these things.

(This post now took 25 minutes to write.)

Ill rephrase my question, because it seems like no-one is getting what Im asking. Basically put I know how routers communicate, how to use HTTPS/Domain names/servers, etc. What Im trying to figure out is how come my professor who doesnt own any website, can use notepad, enter in the text, save/save as it as a(example title) "kitten.html"on his desktop, then exit notepad. Then go to his desktop, click on the notepad file, and it opens up as a webpage in FIREFOX. Yet it doesnt do the same for mine? I know to open up notepad, type in my text, save as (example) dolphin.html, click save, then exit notepad, and navigate to the place where I stored the "dolphin", click on it, and it opens up in IE instead of Firefox?

Oh.

That's a very well phrased question. It never hurts to use more words, that helps us understand what you mean.

I'm not 100% sure of the answer, but I'll bet it's either your default browser setting, or your default file association. I think those are two separate settings, and I'm not sure which governs that particular case.

But try fixing both.

First, open IE or whatever you prefer, and figure out how to set that as your default browser. Probably in Tools->Options.

Then close it and try the file.

If that doesn't work, try right clicking the file and selecting "Open With". Then select IE or whatever, and check the "set this as the default application" box. Hit OK.

If you only want files you make to open in IE, and all the rest to open with Firefox, that gets a bit tougher. What you could do is set up a batch file or something similar which takes a command line parameter and simply opens Firefox, sending it the same parameter. Then set that batch file to be associated with your HTML files, although that might override your default browser settings as well for in-page links. I'm not sure.

There's no doubt an OS-level way to open local files in one browser and remote files in another. I'd google that next if the above options don't work.

In whatever browser, just do File | Open File and navigate to the file you want to open.
That way it doesn't matter what the double-click file association is.

Good point. And once you open it, OP, nothing stops you from copying the URL to your browser of choice and saving it as a bookmark.

...or avoid the needless copy/paste by opening it in your browser of choice in the first place.

You know what I mean, hehe.

Another option is to create a shortcut to Firefox or whatever with the filename as a parameter. Double click the shortcut, boom.

I suggest trying to approach programming from a few fronts. My biggest hurdles in learning were in trying to do too much at once and not taking it slow and consistent.

A) Choose a language related to another one of your interests. In theory, you could use almost any language to do anything, but unless you become interested in the language itself it's unlikely you'll stick with it long enough to get to the "hands on" section.

For example, if you like art the language Processing is a neat one and affordable one! Basically, pick a small end result or break a bigger one down into stages and look for tools suited for the job. There are multiple languages for almost any interest. Look for languages with books you can read samples of online and see if they fit your brain style.

B) Research and experiment with the low levels and underpinnings of programming and work your way up. I feel it's more helpful to read it as an important history lesson than as practical knowledge. You'll see the connections and find them useful when you see them.

A programming language translates (compiles) code into "assembly language", which are special instructions built into the processor.

Assembly language gets translated into binary instructions or 1s and 0s or on and off, like turning a light on and off on an extremely rapid, small scale. The computer processor is fast enough (today, not always the case) that it can perform in what we think of as real time. Important point to note is that by and large the processor works serially that is one after another, rather than side by side.

For the most part the compiler will do a better job than you can. I get wanting to understand, but in some ways it's like trying to understand how the brain processes language in before learning to speak or read. In order to learn that information you have to do those things first.

A computer boots up, from bootstrapping, pulling yourself up by your own bootstraps, a physically impossible task! Like a computer we need a little bootstrapping to get to a place we can learn and understand.

C) Circuit boarding is fun and a nice hands on way to figure out things like logic. For something along the same lines, but more directly related to programming, look up "Arduino projects". It's an affordable entry into physical computing. There are many books with a wide variety of cool projects you can build that will let you get hands on and interactive. Often the tutorials involve audio, movement or blinking lights, which is great for immediate feedback.

As you get more advanced you might need to have some physical dexterity to solder, but I'm a klutz and I manage. There are many women solderers in the modern electronics industry, although they often don't get the respect they deserve (boo outsourcing). You could potentially turn it into a livable job doing electronics repair.

Hope this helps.

Thanks all, it helped :3

This is the only coherent point I can see in this whole thread. Something about kittens, Firefox, and Visual Basic.