This is the /bin/echo command. echo also exists as a command built into the C shell and Bourne shell (see Sections 4 and 5). /bin/echo is the same as the Bourne shell version with one exception: the -n option to /bin/echo works only when the user's PATH variable lists /usr/ucb before /usr/bin. The C-shell version does not support escape characters.
echo "testing printer" | lp
echo "TITLE\nTITLE" > file ; cat doc1 doc2 >> file
echo "Warning: ringing bell \07"