SFTP put BINARY or ASCII

One of the least-understood aspects of FTP transfers is the difference between ASCII and Binary mode data transfers. ASCII stands for American Standard Code for Information Interchange, and is a type of character encoding based on the English language used on devices that handle information stored in text. It includes 33 non-printed control characters and 94 printed characters such as letters and punctuation.

When files are transferred in ASCII mode, the transferred data is considered to contain only ASCII formatted text. The party that is receiving the transferred data is responsible for translating the format of the received text to one that is compatible with their operating system. The most common example of how this is applied pertains to the way Windows and UNIX handle newlines. On a Windows computer, pressing the "enter" key inserts two characters in an ASCII text document - a carriage return (which places the cursor at the beginning of the line) and a line feed (which places the cursor on the line below the current one). On UNIX systems, only a line feed is used. ASCII text formatted for use on UNIX systems does not display properly when viewed on a Windows system and vice versa.

Binary mode refers to transferring files as a binary stream of data. Where ASCII mode may use special control characters to format data, binary mode transmits the raw bytes of the file being transferred. In this way, the file is transferred in its exact original form.