What does 0in mean as a unit of measurement?

I'm going through the code on one of my school's canvas pages and I came across:

<p>&nbsp;</p>
<p>&nbsp;</p>

Can someone explain what 0in means? I can't find it on Google

2 Answers

See CSS values and units from MDN or CSS Values and Units Module Level 4:

in: Inches

… and 0 is just zero.

There are many units of size of margin in HTML such as px (pixel), rem, em, in, etc. The margin: 0in means that the margin has 0 inches from other HTML elements.