Why are there so many pins? That is what is needed for the connections, it was designed that way, if they could have used less pins they would have. If you want to know exactly what those pins are you should be able to find technical specs on the RAM types.
What voltage the RAM runs at you can also find out easily, it depends on the RAM type, just do a web search. DDR2, DDR3 DDR3L, etc... all work on different voltages.