UTF-8, Unicode Characters

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#1

What are UTF-8 Characters?

https://www.w3schools.com/charsets/ref_utf_symbols.asp
How should I use them?

#2

UTF-8 is used for language support, but more specifically - character sets. It’s often used in HTML tag to grab the character set:

<meta charset="utf-8" />

“UTF-8 is unicode based and eliminates the need for server-side logic to individually determine the character encoding for each page served or each incoming form submission.” - (loose quote from W3)

In a nutshell, UTF-8 helps ensure universal browser support for characters beyond ASCII.

Also, you can use the codes to display special characters - the following is a snowman:

<p>&#x2603;</p>

Hope that helps!

One last edit:
More practical use of unicode would be a copyright symbol, ampersand or quotes in some cases:

Ampersand: &amp;
Copyright: &copy;
 Quote: &quot;

wrap them in a html tag to display in your browser.

#3

Official MDN Documentation

Official Character Entity Reference Chart

Character Entities Cheat Sheet