html - Triangle next to the text -

I want to add a small triangle next to the text in a small table. How can I do this? Here's my code:

  & lt; Tr & gt; & Lt; Th st-sort = "firstname" class & gt; Firstname & lt; / Th & gt; & Lt; Th st-sort = "lastname" class & gt; Last name & lt; / Th & gt; & Lt; Th-Saint-sort = "street" class & gt; Street & lt; / Th & gt; & Lt; Th-Saint-sort = "town" class & gt; Town & lt; / Th & gt; & Lt; Th-Saint-sort = "zipcode" class & gt; Zipcode & lt; / Th & gt; & Lt; / TR & gt; Thank you very much for the answer.  

I would suggest that you use this "Font Awesome CSS Framework" for such markings Implementation is very simple and it is also open source.