These articles frequently mentions filename extensions (such as DOC and JPG). Yet many tell me they see no such appendages attached to their files' names. WinXP users can fix this by double-clicking any folder and going to Tools>Folder Options>View and UNchecking "Hide Extensions for Known File Types." Pre-WinXP users find this under View>Options>View.

These extensions have meaning and should NOT be hidden. Here are some examples: EXE/executable file, TXT/plain text file, BMP/bitmap picture, XLS/Excel spreadsheet and PPS/PowerPoint show. A link to a full list of file-name extensions and their meanings are on my home page.

In fact, PC terminology is one of the biggest obstacles to answering questions I receive via email, and why I always post my phone number here.

I could write a book filled with questions such as: "I clicked on a program, but it's too wide for my printer. How do I fix it?"

Worse yet, new terminology seems to appear on a nearly daily basis. Here are a few definitions PC neophytes should learn upfront. A PC's hard drive is a fixed disk made of material more rigid than the "floppy" plastic used on older, removable disks. It was named "C" back when most PCs had two slots ("A" and "B") for removable floppies.

Items on a hard drive (or any type of disk/disc) are either a file or a folder, the latter being recognized by its "yellow folder" icon. Folders contain files and/or other folders, which can contain still other files and folders. Some "system folders" have a different icon, such as the waste basket that designates the "recycle" folder.

Folders do not need file-name extensions. However, if a file's name extension is altered, the file will not perform properly. There are a very few exceptions to this rule, and are explained on my home page.

So, is a "program" a "file"?

Well, a program (aka an "application") can consist of a single file, or it can be a huge collection of files and folders that work together to perform specific tasks. For example, ssstars.scr is a one-file program that generates the "Stars" screen saver. Excel.exe, conversely, is composed of many files and folders, which can do calculations from simple checkbook balancing to plotting the trajectory of a satellite.

Downloading from the Internet - Should You SAVE or RUN?

When you "download a program" via the Internet, you are usually downloading a "setup" file (often named setup.exe) that, when double-clicked, "executes" itself into the application you had in mind. Some setup files have a .zip extension, which must be "unzipped" (decompressed) into the item or items you wanted to download. WinXP has a built-in unzipping program, so this usually happens automatically. Users of pre-XP versions of Windows need a "Zip/Unzip" program such WinZip, available at www.download.com.

Often, after clicking DOWNLOAD, you are asked if you want to RUN or SAVE the file. Choosing RUN will execute the setup file, and create the program you want to use. Clicking SAVE will copy the setup file to your hard drive, where it waits for you to execute it (install the program) with a double-click.