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
