Service mark symbol. The service mark symbol (â ), the letters SM in superscript style) is a symbol used in the United States to provide notice that the preceding mark is a service mark.
Size matters: The micro and mini USB connectors are of similar width. But the micro connector is much thinner (smaller vertical dimension). Some product designs were not able to accommodate the height of the mini receptacle and the new thinner receptacle will encourage and allow thinner products.
So, from this picture, you can see that the Micro USB is slightly wider and shorter, than the Micro HDMI. Hopefully this will help to clear your confusion, and what port that you have... that is, until you only have a Micro USB 2 that also includes MHL functionality. We'll talk about that in another post, though.