In the smarty template file tpl, what is the meaning of "| h" after the variable name when writing and outputting?

In the smarty template file tpl, what is the meaning of "| h" after the variable name when writing and outputting? for example: & lt; p & nbsp; & gt; & lt; input & nbsp; typetext & nbsp; disableddisabled & nbsp; namestate & nbsp; value & lt ;! -- {$ ArrForm. state | h} -- & gt what is the meaning of "| h" after the variable name in the tpl file of the smarty template?
For example:

What is h after the variable in red?

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Pipeline (borrow operating system terms)
Pass Template variables to functions
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$ ArrForm. state
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H
Equivalent
H ($ arrForm. state)

That's what he agreed. there's no reason at all.
You 'd better read the manual twice first.