This command echos the args to the current output stream. This is normally stdout but can be set to a variety of channels. If an arg is -nonewline then no newline is printed at the end of the printed strings. Otherwise a newline is printed after printing all the given args. For the full details of the redirection, see the command output-strings-destination.
Users wanting to print variables and data to the screen, should use echo rather than the Tcl command "puts." The echo command gets redirected to the appropriate channel according to output-strings-destination; the "puts" command does not.