nl command in Linux is a utility for numbering lines in a text file. Also known as 'number lines', it can be handy when you need an overview where certain lines in a file are located. By default, nl number the non-empty lines only, but this behavior can be modified based on user's needs.
It follows a syntax like this:
nl [options] [file_name]
If no file is specified, nl will wait for input from user's terminal (stdin). Its clear and readable output makes it a valuable part of any Linux user's text processing toolkit.
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