The Simple File Transfer Protocol (SFTP) is a network protocol used to transfer files securely over a computer network. It operates on the SSH (Secure Shell) protocol, which provides a secure channel for data transmission. SFTP allows users to upload, download, and manage files on remote servers while ensuring that the data remains encrypted and protected from unauthorized access. SFTP is commonly used by system administrators and developers to manage files on web servers and cloud storage. It supports various file operations, including file transfer, directory listing, and file permission management, making it a versatile tool for secure file handling in different environments.