How and where does Altcoin compare to Bitcoin and Ethereum? There are also two ways to trade and buy from individuals. Personally, I will not say more lengths, as it is similar to BTC, ETH. You can also buy Altcoin directly in USD, Visa, Paypal on many trading floors, but this section will guide you to buy Altcoin on both floors Bittrex and Poloniex, two trading floors large volume The most prestigious and leading today, I also play trade coin on these two floors. But these two floors you do not buy directly in US dollars through visa, master or Paypal that have to buy ETH, BTC or USDT can be traded and the most popular is still Bitcoin.