Navigating Your Computer: Part 1

When you consider that computers can hold thousands or millions of files, it seems necessary for there to be some sort of organization to help you (and the computer) find what you (and the computer) are looking for.  The organizational structure used on modern computers is sometimes referred to as a file hierarchy.  There are 3 main parts to the structure: files, folders, and drives.

You already are pretty well-acquainted with the concept of a file—it holds the information for a particular task, whether it's a song file, a word processing file, or an application (or executable) file.

If the entire organization were just files in a big virtual bucket, though, it would be almost impossible to find a particular file.  Consider trying to scan a list of one million file names for that particular song (whose name you might not even correctly remember) you are looking for.  Impossible! (or at least really really time-consuming.)  Also, you would not be able to call two files the same name, which is a huge problem.  What if I am working on two papers, and want to have a file for each called "Draft.doc," "Bibliography.doc," and "Final.doc?"  The computer (and I) would not be able to tell the two sets of files apart, and bad stuff would happen.  To avoid this problem, we use the concept of folders, or directories.

The analogy between computer folders and real folders is extremely direct: just as a file is like a piece of paper (or a few pieces stapled together), so too is a folder like the manila folder you use to keep a bunch of related papers together.  Folders make organization on a computer so much easier because inside a folder, you can create another folder, and inside that one another, and so on almost indefinitely.  Consequently, to continue my earlier example, if I have two papers to write, I can create a folder called "First Paper" and a folder called "Second Paper."  I can then put the files for the respective papers inside their respective folders.  Specifically, I can have a file called "Draft.doc" that's inside the folder "First Paper," and a different file called "Draft.doc" inside "Second Paper."  Both the computer and I can now tell the two files apart because the "Draft.doc" inside "First Paper" is in a different folder than the one in "Second Paper."  (Note: directory and folder are completely synonymous.)

For most intents and purposes, files and folders are sufficient to keep a computer organized.  However, there are some times when things get a little bit more complicated.  For example, if you have a digital camera, you probably will at some point want to connect it to your computer so you can save the pictures you took and email them to friends and family.  To do that, you need to be able to tell your computer to copy the files from the camera onto the computer's hard drive (remember, that's where the computer's files and folders are stored).  However, the pictures are on the camera, not on the computer, so you won't be able to find it just looking through the folders and files on your computer.  To resolve this problem, we use the concept of drives or disks (again, synonymous).

Most computers today have one hard drive that stores all of the computer's files, folders, and applications.  Other devices have hard drives as well: cameras, mp3 players and iPods, cell phones, and other similar devices.  When you connect one of these to your computer, the computer recognizes it as a new hard drive.  To continue the files/folders analogy, your computer's hard drive is like your desk, with all of the papers and folders that you normally use on it.  Every so often, though, the office mail gets delivered in a box that the mailman leaves on your desk.  Inside the box are more files and folders, similar to the ones that are on your desk.  Even the box itself is on your desk.  But it's clear that the stuff in the box is separate from the stuff on your desk.  In the same way, your computer presents all of the files and folders on its own hard drive separately from the stuff in a different drive.  Another way to see the difference between folders and drives is that different folders are on the same piece of hardware, but different drives are on different pieces of hardware.

Examples

On an Apple computer, the icons used to represent files look like this: 

Depending on the file's extension (type), there might be a picture on the icon that tells you what type of file it is.

Folders look like this:

Some folders have special pictures on them that tell you what kinds of files are in them.  For example, the "Applications" folder has an "A" on the icon, and the "System" folder has an "X" (for Mac OS X).  On Windows computers, the "Desktop" folder looks like, well, a desktop.

Drives can have different icons depending on what kind of drive, and on whether you're on a Windows or Apple computer, but they usually look something like one of these two:

Notice how the first drive is called "Macintosh HD."  This is the computer's own hard drive (HD stands for hard drive).  The one called "Music HD" is a separate drive that has music files on it.  Different kinds of drives can have different "labels" on the icons, but those two are pretty generic.

Up Next: Navigating Your Computer: Part 2

Files and Extensions

A file is a set of computer code (software) that contains all of the information necessary to complete a particular task.  There are different kinds (or types) of files, denoted by different extensions, which consist of a period followed by (usually) three letters that abbreviate the kind of the file.

Examples
Applications are files, and they are denoted by the .app extension on Mac OS X, and by the .exe extension on Windows (.exe stands for "executable file").  Other common files are Microsoft Word files, which contain whatever you wrote on Microsoft word.  These have the .doc and .docx extension (both stand for "document," but the x in .docx is to distinguish the newer version of Word from previous ones).  Here are some others:

• Microsoft Excel: .xls and .xlsx
• Microsoft PowerPoint: .ppt and .pptx
• MP3 and AAC (music files): .mp3 and .aac
• MPEG (video files): .m4p and .mp4
• Web Pages: .htm and .html
• Plain Text (i.e. without formatting like color, size, font): .txt
• JPEG, GIF, TIFF, RAW (images/pictures): .jpg, .gif, .tif, .raw
• PDF (Portable Document Format): .pdf

Tomorrow: Revisit some previous topics with our new tech-lingo

Cut, Copy, and Paste

One of the reasons that computers are better than typewriters is that computers can copy bits and bytes extremely quickly.


Cut, copy, and paste are three commands you can get to from the "Edit" menu (post forthcoming), located next to the File menu.  These three commands make use of the computer's "clipboard," a place that can temporarily save text (words, numbers, and symbols), images (pictures and icons), and in some cases other sorts of information.  Copying information puts it into the clipboard (for future use).  Cutting information puts it into the clipboard and deletes it from its original location.  Pasting information takes whatever is on the clipboard and inserts it where your cursor is.  (You can move the cursor's location by clicking the mouse pointer where you want to paste the information).


When you copy or cut, any information that was on the clipboard is erased from the clipboard, so it is not possible to copy (or cut) two or more different things at the same time.


The cut command is identical to copying then deleting—it's just faster.


Examples
If I am reading a web page and notice a great quotation that I could use in a report I'm writing, I can copy the quotation from the webpage and paste it into a word processing application (like Microsoft Word or Apple's Pages).


If I am trying to arrange the paragraphs on my report, I can cut a paragraph from its original location (thereby deleting it), and paste it where it belongs.


Tomorrow: Select and Highlight

Windows and Tabs

A window is part of an application that takes up space on the computer screen.  Windows can be moved around the screen, revealing other parts of the computer screen that were previously hidden by the window.  Windows can be thought of as pieces of paper lying on a table.  Each page has some information on it, and if you have a lot of pages on the table, you can stack them up so you only see the topmost page, or spread them out so you can see different parts of different pages at the same time.

Unlike physical pieces of paper, windows can be resized to take up more or less space.  They can also be "minimized," where they are temporarily hidden from view, "maximized," where they take up the entire screen, and "closed," where the page and its contents are removed from view.  (Recall that "Close" is a command in the File menu).  Also, computers are designed only to focus on one window at a time.  Unfocused (or unselected) windows will usually have faded colors, whereas the one in focus will have normal colors.  This is to ensure that, for example, when you choose "Close" from the File menu, you close the window that you intend to, namely the one in focus.

On computers running the Microsoft Windows operating system, the three buttons for minimizing, maximizing, and closing windows are in the upper-right corner of each window.  On computers running Mac OS X, the buttons are in the upper-left corner of each window.  Be aware that on Macs, the green "maximize" button does not actually expand the window to occupy the entire screen.  Rather, it resizes the window to "fit" whatever the window contains, so there is no blank space surrounding a photograph being viewed, for example.

Some windows, on both operating systems, are missing some of the "size control" buttons.  Usually, the "maximize" button will be the one missing because it would not make sense to maximize those windows.

A tab is a relatively new feature introduced to web browsers (Safari, Internet Explorer, Firefox, etc.) to help organize the application when people want to have many web pages open at the same time.  Instead of having one window for each different webpage, people can put multiple webpages in the same window by having each webpage be a different tab on that window.  At first glance, this feature may seem useless, but its usefulness shows when, for example, you have five different webpages that you want to minimize or close.  If they are in different windows, you would have to close each one individually, but if they are five tabs all in the same window, you only have to close one window instead of five.

Examples
The three "size control" buttons on a computer running Mac OS X:

And on a Windows computer:

Different tabs as they appear in the web browser Google Chrome:

Notice how only one tab can be "selected" or "focused" at once (in this case the "New York Times" tab).

Tomorrow: Cut, Copy, and Paste

Operating System

An operating system is an application (piece of software) that acts as an interface between the computer's hardware and other applications on the computer.  It is also responsible for coordinating what happens when the computer turns on and off.  While it is possible to have two or more operating systems on a single computer, most computers only have one.


Examples
The two most popular operating systems are Microsoft Windows (XP, Vista, and 7)

 and 

Apple Mac OS X (Tiger, Leopard, and Snow Leopard).






A third operating system that is gaining popularity is called Linux, and it comes in widely varying varieties, called "distributions."  The most popular distribution is called Ubuntu (pronounced "oo-boon-two").  Ubuntu is the distribution most similar to Windows and Mac OS X, while other distributions are much more complicated to run, and are mainly used by computer programmers and other people who like to tinker with computers.


Tomorrow: The Internet!

Keyboard

A keyboard is an input that allows you to input letters, numbers, and symbols into a computer. It also has special keys called "modifier keys" such as Shift, Control (or ctrl), Alternate (or alt), Function (fn), Command (z) or Apple ().  These keys do not produce letters or symbols when you push them.  Rather, they change what happens when you push other keys at the same time.

• The Shift key changes lowercase letter keys to capital letter keys, and changes number keys to symbol keys.  For example, pressing the A key gives "a," but pressing shift and A gives "A."
• On a Windows computer (Dell, HP, Toshiba, Sony), the Control key, in combination with another key, can perform an action, similar to the "function keys" below.  For example, pushing Control and s at the same time will save your current work on the computer.  Control and p will print the current page.
• On an Apple computer, the Control key is not used often.
• The alt or option keys change both letters and numbers to other characters.  For example, pressing option and s gives "ß," or option and t gives "†."
• The fn key is not used often.

Keyboards also have "function keys," which are usually in the row above the number keys.  Function keys are labeled F1 through F12, and when you push them, they have the computer perform a certain action (other than typing a letter).  Finally, the Escape key (esc) can do different things depending on the particular computer and keyboard.


Example

The Apple Keyboard

Notice the shift, fn, control, alt/option, and command "modifier" keys in the lower-left corner.  Also notice the "function" keys on the top row, some of which are labeled with their intended "actions," or functions.


Tomorrow: Mouse and Trackpad