Updated: Apr 8, 2018
So, Bitcoin is the only way to trade, right? Wrong.
If you have logged onto an exchange, you may notice that coins are broken into different categories to purchase. In the illustration above (from Bittrex exchange), there are Bitcoin (BTC), Ethereum (ETH) and Tether (USDT) markets. Some, not all, exchanges even have their own coin. For example, Binance has their own coin; BNB. Kucoin also has their own coin. You will notice that the prices and volume are also different. I'll be honest, I rarely trade in anything other than Bitcoin but it's a personal preference. This is really a more advanced topic, but it's worth noting and pointing out so you will know what they are. As you get more experienced, there may be instances where you will trade in other combinations other than BTC. You should just be aware of the differences on each exchange.