A recent AIDS special noted the trans-mutability of the virus...what mechanism is inherent in it's mRNA?

The ability of the AIDS virus to mutate within a host environment fascinates me. It seems as though this small piece of genetic material has a process of survival that appears to be deliberate. It is as though by design. This is evidenced by the constant mutations which effect its' survival. What process's are at play.? [those not addressed obviously in the detail of the question]

mrchinlersir: thank you, but I am hoping to find a process and not a mechanism. The action you detail is understandable in so much as it relates to a cause/effect result subsequent molecular structure. I would like to hear of something more gobal,something that suggests a possible answer to the virus's overall process. How does it ''know'' how and when to modify itself? My question is probably more philosophical, but your answer was nevertheless 'superb'.

HIV is a retrovirus. Its genetic material is RNA, but it does not have a 5' cap, nor a 3' poly adenylation, so it cannot act directly like mRNA as the other positive sense RNA viruses do. Instead it also brings a reverse transcriptase with it that takes the single stranded RNA genome and turns it into a Double stranded DNA piece that must be inserted into the host genome, then it is reliant on the host to transcribe and translate it. The RNA genome is very easily destroyed by host enzymes, so the reverse transcriptase must work very quickly to change the RNA to DNA, and the extra speed causes mistakes, which are manifested as mutations.

most DNA and RNA have a process where they are able to "spellcheck" gene sequences, however the HIV virus does not and the constant mutation is a result of the fact that it does not have a need for one specific sequence, but there are many genetic variations.