Everybody knows about ETH and BTC now. And Dogecoin, but are there any others that we should look at and invest? Which ones and why? Some of these coins I understand they are backed up by limited numbers (BTC) which gives them anti-inflation properties, some are backed by ecosystems (\*which I really don't understand) and some seem to be totally random like Dogecoin... What makes a coin a great coin to own, is there a formula involving market cap, volume and supply?