Windows allows the user to enter far more characters than exist on the keyboard, and these symbols are hardcoded into the system as Unicode alphanumeric data. They do not change from one version of Microsoft Word to the next, nor from one version of Windows to the next.
To enter a special Unicode character, you need a keyboard with a right-side number pad. To type a special character, you need to hold the Alt key and press a special four-digit sequence that represents the Unicode character. Releasing the Alt key inserts the character into the document. In Word, you can also use the Insert Symbol function.