Changes

# Issue the following linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">sed 'p' data.txt</span><br><br>You should notice that each line appears twice. The reason why standard output appears twice is that the sed command (without the -n option) displays all lines regardless if they had been specified as a pattern.

# Issue the following linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">sed -n 'p' data.txt</span><br><br>What do you notice?<br><br>You can specify an address (line #, line #s or range of line #s) when using the sed utility.<br><br>