cat is a command to concatenate or display text files, when it displays files...

cat is a command to concatenate or display text files, when it displays files it just runs from the the top to the bottom without navigation options. In /etc/passwd you are viewing the password file which contains the basic user information which is username, x (represents that the password is in the shadow file), user id, primary group id, home directory, login shell.

The less command outputs a text file, but allow you to navigate back and forth in the file using the arrows and page up/page down keys.

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