NAME
echo —
    write arguments to the standard
    output
SYNOPSIS
| echo | [ -n] [string ...] | 
DESCRIPTION
The echo utility writes any specified
    operands, separated by single blank (‘ ’) characters
    and followed by a newline (‘\n’) character, to the standard
    output.
When no operands are given, only the newline is written. The -- operand, which generally denotes an end to option processing, is treated as part of string.
The options are as follows:
- -n
- Do not print the trailing newline character.
EXIT STATUS
The echo utility exits 0 on
    success, and >0 if an error occurs.
SEE ALSO
STANDARDS
The echo utility is compliant with the
    IEEE Std 1003.1-2008 (“POSIX.1”)
    specification.
The flag [-n] conflicts with the behaviour
    mandated by the X/Open System Interfaces option of the IEEE
    Std 1003.1-2008 (“POSIX.1”) specification, which says
    it should be treated as part of string. Additionally,
    echo does not support any of the backslash character
    sequences mandated by XSI.
echo also exists as a built-in to
    csh(1) and ksh(1), though with a different syntax.
Where portability is paramount, use printf(1).
HISTORY
An echo utility appeared in
    Version 2 AT&T UNIX.