Why is the hash part of the URL not available on the server side?

Why is the hash part of the URL not available on the server side?

php javascript url hash href

php

Add http:// prefix to URL when missing

php http html anchor href

php

Add PHP variable inside echo statement as href link address?

php variables echo href double-quotes

php

How to write the code for the back button?

php button href

php

PHP Xpath : get all href values that contain needle

php xpath href

php

joomla BASE HREF uses HTTP instead of HTTPS

php apache joomla href http-status-code-303

php

PHP extract link from <a> tag [duplicate]

php string hyperlink extract href

php

Insert php variable in a href

php href

php