Now here is where I start to get confused. Bitcoin was the starting currency, but how do things like Litecoin and Dogecoin factor in to it? Are they entirely separate currencies, or are they linked in some way? The reason for asking is sort of explained in my post above - if they are entirely different then it requires backing and acknowledgement from the world in order to be worth anything. Again, such reasons are why I'm holding back for now.
a lot of the Cryptocurrencies use the same hash so if you're mining for one you can mine for the others using no more processing.