For more information about SSH, refer to the following resources.
The /usr/share/doc/openssh- directory — Replace <version-number>/<version-number> with the installed version of the OpenSSH package. This directory contains a README with basic information about the OpenSSH project and a file called RFC.nroff with general information about the SSH protocol.
SSH related man pages — There are a number of man pages for the various applications and configuration files involved with SSH. The following is a list of some of the more important man pages.
man ssh — Describes how to use this command to connect to an SSH server.
man scp — Describes how to use this command to copy files to and from an SSH server.
man sftp — Describes how to use this command to interactively copy files to and from and SSH server.
man sshd — Describes available command line options for the SSH server.
man ssh_config — Describes the format and options available within the configuration file for SSH clients.
man sshd_config — Describes the format and options available within the configuration file for the SSH server.