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In the category of small commands,
we also have cat and tag.

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Let's talk about it. Cat has
some nice options to show you.

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Text files minus uppercase H
shows all non printable characters.

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And B is
giving line numbers.

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And N is doing the
same, but not for empty lines.

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And S can be used
to suppress repeated empty lines.

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Tag, in fact, is not the most useful
utility. It's like cat, but in the reverse order.

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So let
me show you.

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So when I use cat on regex, then
I'm just seeing the content of this regex file.

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And what else did
we have? Hey, LS LRT

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demofeld. That was a
masterwork of art, right?

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So let me use
Cat A on demofell.

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And what do we see? We see these dollars.
The dollar is every time that we used enter.

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So what else can we do?
Well, we use cat on regex.

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You can also
use tack on regex.

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And what do we see? It's the reverse content of
the regexval. Does that make sense? No, not at all.

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It more sounds like an exercise
in an introduction to C programming course.

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But it's here. And sometimes on
Linux you have commands and utilities that

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were created just because the developer
thought it was fun to create them.