Files, Files, Files

What are all those strange files you find on the Internet?

If you're new to the Internet, you won't want to miss out on the array of software, music and other goodies that you can download and use on your own computer. Before you get started, you'll need to know a little something about the many file types that you'll encounter.

The following overview won't make you an expert, but perhaps it'll clarify some of the confusion.

HTML or HTM Files

HTML files -- ending with .html or .htm -- are the files that are used to produce web pages. For example, you might find an HTML file named bird.html or bird.htm. HTML files contain coding information that can be read by a web browser.

The source coding that comprises an HTML file appears to be a combination of gibberish and the English language. However, if you look at the HTML file in a web browser, you see the visual components that the coding is calling for -- color, style, fonts and possibly pictures or sound. If you find a web page that interests you, you can save it to your desktop and then open it in your browser later.

The good thing about HTML files is that they will work on any computer and will open in any browser -- regardless of whether you are using a Mac, a PC, or any other machine.

Doc Files

Files ending with .doc are created in Microsoft Word. They can contain styling effects, color, special fonts, images, tables, lists and all of the various effects that you can produce in a powerful word processing program.

If you download a .doc file, you must have the correct software on your hard disk before you can open it. If you are using MS Word, you will be able to open the file only if your version of Word is the same or newer than the version of Word that was used to create the file. (Remember that WordPad is not the same as MS Word and will not open a .doc file). WordPerfect might be able to import the file, but expect to see some loss of formatting.

If you don't have Word or WordPerfect, you can download a free Word Viewer from Microsoft's Web site. This allows you to view the file, but not write to it. Doc files can contain macro viruses -- so always run a virus check before opening one that you have downloaded.

PDF Files (Portable Document Format)

PDF Files, developed by Adobe Systems Inc., are a format for developing and publishing electronic documents. PDF files are cross platform -- you can open and read them in whatever computer you are using.

PDF files can contain powerful formatting features including text, images, sound, hyperlinks and search capabilities. However, PDF files cannot be opened unless you have installed Acrobat Reader -- available free from Adobe's web site. Your version of Acrobat Reader must be updated from time to time to allow you to access the newer PDF files that are made available on the Net.

You can read (i.e. view) a PDF file, but you cannot write to it (i.e. make changes to it.)

EXE Files (Executable)

Files ending in .exe are "executable" -- meaning they are standalone software programs that will " run" without any special software, readers or plug-ins. Most of the software that is free or for sale on the Net comes as an .exe file. If Windows users inspect the files on their hard disk, they will discover that almost every folder containing a software application has a file that ends in .exe. This is the software's "motor", if you will. Once downloaded, many exe files must be installed on your computer before they will "run".

There are a couple of things to keep in mind about .exe files. First, they can contain viruses. Always perform a virus scan before running a new .exe file. Secondly, .exe files do not work on the Mac. They are Windows applications, and they may be specifically programmed to work on one Windows operating system, but not on another. Remember to check the system requirements before downloading to be sure that your new .exe file is compatible with your system.

Zip Files

Zip files, ending with the three-letter extension of .zip, are files that have been compressed into an "archive" to save space. Many files available on the Net are large -- and the download time will be huge.

To save time and space, file publishers often use a special compression program that reduces the number of byes and therefore speeds up download time. To open a Zip file, you must have e a special software application installed on your computer. WinZip (www.winzip.com) is among the best known applications for this purpose. WinZip will "decompress" the file or files that are contained in the .zip, allowing you to open them in the usual way.

Mac users will need a special utility that allows zip files to be opened with Stuffit --a compression utility included with the newer versions of the Mac OS.

.Sit Files

Sit Files are McIntosh files that have been compressed into an archive using a utility such as Stuffit. Like Zip files, Sit files are compressed to save space. Mac users will need to have Stuffit running on their system, and PC users will need a special software utility such as Stuffit Dropstuff or Unsit.

.SEA Files

These files are Macintosh Self Extracting Archives. They are essentially .Sit files with programming included that allows the Mac user to open the files without having any special software installed on the system. Windows users will need a program like Stuffing Enhancer before they can run SEA files.

.HQX and. BIN Files

.HQZ (Binhex) and .Bin (MacBinary) files are Macintosh files that have been translated (coded) into a special format so they can be stored or transferred on other computers (i.e. Unix or Windows). Both files must be "decoded" or "unencoded" before they can be used.

MacBinary files must be decoded once they are downloaded from the Web. Most Mac telecommunications programs can decode MacBinary files to standard Mac files as they download, provided they are told in advance to perform this task. Windows users will require a special utility such as MacWin before they can open a binary file. When downloading a MacBinary file by FTP, always use the Binary protocol option, never ASCII or text.

.HQX files are translated into ASCII characters which can be handled by almost any system.

Gifs and JPEGs (or .jpgs)

Files ending in .gif, .jpeg, or .jpg are image files (pictures or drawings) that have been compressed into a format that is suitable for display on the Internet. Gifs and JPEGs have a low resolution that reduces file size and speeds up Internet download. The low image quality makes them suitable for viewing on the computer but they will not result in a good printout.

Gifs or JPEGs are cross platform -- meaning you can view them on any computer. If you are viewing these files from a web page, your browser reads them for you. However, if someone sends you a gif or a jpeg as an email attachment, you will need a graphic software application installed on your computer before you can open them.

.TXT (Text files)

Text files (sometimes called "ascii") end in the three letter extension of .txt. Text files are basic, plain files that contain no special formatting. Therefore, expect no color, no fancy fonts, no bullets, no pictures and no tables. On the other hand, text files are small, cross platform and can be read by any computer and any operating system. If someone sends you a file ending in .txt, you can open it in NotePad, WordPad, SimpleText, or any word processor.

. RFT Files (Rich Text Files)

RTF files are sophisticated versions of Text Files. Rich Text files may contain fonts, color and added effects, but they do not contain the more sophisticated style effects that you can get with a word processor. Rich Text files can be opened in WordPad and in more recent versions of word processing programs. They are more attractive then .txt files, but less flexible than a file created in a word processor. Rich text files or plain text files cannot contain viruses.

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