In html some chars are reserved, it means that the browser will see them as formating command or html tags. In order to have them displayed, you need to replace them with character entities.
< is replaced with <
> is replaced with >
& is replaced with &
so
<h1> Hello </h1>
is replaced with
<h1> Hello </h1>
To see some text in this question box, use button 'encode' once.
<h1> Hello </h1>
To see the code in published question, use button 'encode' twice.
<h1> Hello </h1>
HTML Entities[
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