Data transferred over FTP is sent in ASCII, binary, EBCDIC or local modes. Most of the FTP clients automatically determine the data transfer mode based on the contents or extension of the file.
Audio, video and image files are generally transferred in binary mode, whereas HTML, script and text files are transferred in the ASCII mode.
Computers with identical setups transfer data in the local mode, and hosts using the EBCDIC character set use the EBCDIC mode for data transfer.