Fetch Help > Preferences > Upload

Preferences in the Upload Preferences affect the format and names of files uploaded with Fetch.

Default upload format
  This pop-up menu lets you choose the format to use when uploading files. Usually you should use Automatic, where Fetch will try to determine the right format to use by examining the file in question. You can learn more about the other choices in the upload formats help topic.
  You can temporarily override this setting using the Format submenu in the Remote menu. You can also temporarily override it in the choose file prompt when you use the Put command.
  Automatic is the default setting.
Add filename extension when uploading: BinHex files
  If this box is checked, Fetch will add an ".hqx" extension to the names of files uploaded in BinHex format. The ".hqx" extension will be added in addition to any existing extension a file might have. Using this common extension makes it more likely that the files will be retrieved intact when downloaded again. Checked by default.
Add filename extension when uploading: MacBinary files
  If this box is checked, Fetch will add a ".bin" extension to the names of files being uploaded in MacBinary format. The ".bin" extension will be added in addition to any existing extension a file might have. Using this common extension makes it more likely that the files will be retrieved intact when downloaded again. Checked by default.
Add filename extension when uploading: Text files
  If this box is checked, Fetch will add an appropriate extension to the names of files being uploaded in Text format (for example, ".txt" for text files, ".html" for HTML files, ".c" for C files, and so forth), if the files don't already have an extension. Using these common extensions makes it more likely that text files will be retrieved intact when downloaded again. Unchecked by default.
Add filename extension when uploading: Other files
  If this box is checked, Fetch will add an appropriate extension to the names of files being uploaded in Binary (Raw Data) format, if the files don't already have an extension. For example, ".jpg" will be added to JPEG files, ".doc" to Microsoft Word files, and so forth. Many systems determine the type of a file from its name extension; for example, a JPEG file is handled better when its name ends in ".jpg". Unchecked by default.