Binary mode and ASCII mode refer to two ways an FTP program can transmit files. Certain kinds of files are better suited to each mode.

Fortunately, most FTP tools include a third mode: an "auto" or automatic option, which decides for you which mode to use when uploading a file, so you don't have to think about it.

If your tool does not include this option, you can decide which mode to use based on these guidelines:

• Use ASCII mode for files that contain all text (such as HTML or text files).
• Use binary mode for images and other media files, such as videos.