Your best friend for file transfer.Fetch
FTP and SFTP (the protocols Fetch uses to transfer files) divide files into two categories: text (ASCII) files and binary files. Furthermore, the Macintosh uses complex files that require the use of special formats when transferred to other types of computers. These issues must be considered in order for a file transfer to be successful. Fetch has three download modes that control the way a file is retrieved — they are titled Automatic, Text, and Binary.
You can set which download mode Fetch will initially use for all transfer windows with the Default download mode preference in the Download Preferences pane. You can change the download mode temporarily for a transfer window with the Mode submenu in the Remote menu.
If a binary file (such as a JPEG file) is downloaded as a text file, it will become corrupted and unusable, so it's important to use the right mode. Fetch has an Automatic download mode that works well for most situations so that you don't have to decide each time. Unfortunately, Fetch cannot always tell what sort of file it is downloading and treat it in the appropriate way, so some of the time you may have to specify what sort of file you are getting. The three possible settings are explained below.
Fetch starts out with the Automatic mode selected, and this mode will be the right one most of the time. When Automatic mode is selected, Fetch uses the filename extension of the file you are getting to determine what to do. For instance, text files usually have the extension ".txt," and JPEG files end in ".jpg". This information leads Fetch to download ".txt" files as text files and download ".jpg" files as binary files. Fetch comes with a default set of mappings of filename extensions to the appropriate download modes, and it also uses information from the operating system and the Transfer Options pane of the info window to decide the correct download mode. See the Transfer Options help topic for more information.
Some files do not offer any clues because they don't have extensions, and in that case Fetch will use its default fallback behavior (initially, Binary mode). You can change the fallback behavior by selecting a file without an extension, choosing Remote > Get Info, and in the Transfer Options pane, choosing either Text or Binary from the Get files like this as menu.
Fetch can automatically recognize and decode certain kinds of encoded files after downloading them — BinHex, AppleSingle, and MacBinary files, as well as StuffIt X archives, Zip archives, Gzip compressed files, and Gzipped Tar archives. When Fetch detects an encoded file, it automatically decodes the file unless you set the Transfer Options in the info window to not decode that kind of file, or if the Allow automatic decoding of downloaded files checkbox in the Download Preferences pane is unchecked.
The Automatic setting may do the wrong thing if the filename doesn't give enough information about the file kind, or suggests the wrong file kind, for example a ".txt" file that is in fact a binary file. For these situations, you must use one of the other two settings.
This setting tells Fetch to assume downloaded files are text files (or BinHex files, which are a kind of text file). Text files are also known as ASCII files. When a text file is downloaded, line endings will be converted according to the Text file line endings preference in the Download Preferences pane. If a text file you're downloading has the sort of name usually associated with binary files (for example, ending in "bin", "Z", "sit", "gif", or "tar"), you should choose this setting to override the automatic behavior.
This setting is for getting binary (non-text) files, specifically those files whose names do not identify them as being binary files. If you know that a file is not a text file (for instance, it is in MacBinary or AppleSingle format), choosing this setting will help ensure the proper treatment. When this mode is chosen, the downloaded file will be checked to see if it is in MacBinary or AppleSingle format.