Smiley images and the text used to produce them*:
In some instances, multiple text options are available to display the same smiley.
Why Doesn’t it Work for Me?
If smileys work for others at your site but not for you:
Type a space before and after your smiley text. That prevents the smiley being accidentally included in the text around it. 😳
Make sure not to use quotes or other punctuation marks before and after the smiley text. 🙄
via Using Smilies « WordPress Codex.
This is just for personal reference.