Why do symbols like apostrophes and hyphens get replaced with black diamonds on my website?

Question

A website I\'ve made has a few problems... On one of the pages, wherever there\'s an apostrophe (\') or a dash (-), the symbol gets replaced with a

Answer 1

What I really don't understand with this kind of problem is that the html page I ran as a local file displayed perfectly in Chromium browser, but as soon as I uploaded it to my website, it produced this error.

Even stranger, it displayed perfectly in the Vivaldi browser whether displayed from the local or remote file.

Is this something to do with the way Chromium reads the character set? But why only with a remote file?

I fixed the problem by retyping the text in a simple text editor and making sure the single quote mark was the one I used.