So HIV is a human virus, is a virus that infects human cells and it stands for human immunodeficiency virus and it can basically lead to AIDS. Now, basically the way that the HIV system looks like is as following. We have our single stranded RNA molecules shown in red, found inside the protein capsid shown in green. And inside that capsid we also have different types of proteins. We have a specific type of protein known as reverse transcriptase, which is basically a protein enzyme that acts to transcribe RNA into DNA as we'll see in just a moment. Now, the HIV also contains the purple lipidrich layer and this purple lipid rich layer contains protrusions which are basically receptors which will bind to the protein receptors found on the cell membrane of the human cell.