Identifying Common File Types in Use on the Internet All programs listed in blue available for downloading
Common File Types Found on the Internet
Text:
Text files are generally created equal (and denoted with a .txt suffix) until you bring them "down" from the Internet. At that point your software may have inserted "hard returns" at the end of each line. The best method of cleaning up files like this before importing them is to download them using a different application (remember that Web browsers support all protocols) so no cleanup is necessary. Short of that, get a copy of Add/Strip (click to download), a shareware product that makes cleaning up these text files an automatic process.
Sound:
Sound files are typically in an uncompressed UNIX format (.au or .aif suffix). Web browsers can recognize these data files with "helper" applications such as Sound Machine, SoundApp and UlawPlay. The next most prominent file types are the DOS WAV format and the MOD music format. These and many other sound files are typically compressed and need to be uncompressed before they can be used. Once uncompressed, very few Macintosh programs can recognize these DOS file types directly - HyperStudio is one software program that needs no translation program to use almost all types of sound files found on the Internet once they're uncompressed. A final sound type that is plentiful is the MIDI type, particularly since QuickTime supports them directly. The application All MIDI makes quick work of converting native MIDI files into QuickTime.
Graphics:
The most widely used graphic file type is GIF (Graphics Interchange Format, pronounced "jiff", like the peanut butter). Within the past year the JPEG format, which offers more colors and greater compression, has seen a tremendous growth in use. Web browsers can typically display these graphic types as inline images without "helper" applications. When retrieved as a file via a URL however, these types often require a helper application to display the graphic. JPEGView is the most widely used graphic "helper", although GIFConverter can also be used and offers some additional features. Other, less often used graphic types include PICT, TIFF, and BMP. These types are typically in compressed format similar to sound files. Once these files are retrieved and uncompressed, HyperStudio is one of the few software programs that recognizes these varied file types directly. If you have a need to regularly convert between a wide variety of graphic file types, then Graphic Converter is the application for you.
Movies:
Movies generally come in a UNIX "flattened" QuickTime format (.mov suffix). All Web browsers require a "helper" application to play these movies (such as Fast Player or Apple's MoviePlayer). Another favorite movie type is MPEG (.mpg suffix). This is a compression scheme that is generic to all computer platforms in comparison to QuickTime, which is a proprietary technology from Apple. MPEG movies often do not contain sound and do not compress as tightly as QuickTime movies. Sparkle is the most preferred "helper" application that plays MPEG movies. The latest format is Apple's QuickTime Virtual Reality (VR) which supports panoramic views. QTVR Player is necessary to view these files.
Compression:
Any file that is not a "generic", supported UNIX format typically is compressed using a software technique native to the platform on which the file was created. On the Macintosh side, that typically means the programs StuffIt (.sit suffix) or CompactPro (.cpt suffix) were used. For most of your Internet uses, the freeware program StuffIt Expander works fine and is automatically recognized as a "helper" application by most browsers. Any file which includes the ".sea" suffix is a self-extracting archive which means it contains the necessary application to uncompress itself. On the DOS side of things, you'll usually see suffixes of ".zip" or ".lha" for compressed files. Since many DOS sound, graphic and animation files can also be used directly by a few Macintosh programs, you'll be interested to know that shareware programs such as MacLHA and ZipIt are available to uncompress those DOS files on your Macintosh. In addition, the commercial program, StuffIt Deluxe, also includes translators which allows it to decompress many DOS formats.
