Use the references on the next two pages to find the symbols you need. When Using Character Entities Forgetting to add the closing semi-colon. Character entity references work in many situations without the semi-colon, but not in others. It's easier to always put the closing semi-colon than to keep track of the situations where it's not required. Putting the names in the wrong case.
Names are case sensitive.
Mostly they are in lower-case, but not always.